When do we say "You little liar" and "You big liar"?
Do the words "little" and "big" mean what they mean?
"You little liar" mean "You tell small and not so serious lies"
and
"You big liar" mean "You tell big and serious lies"
Or "little liar" and "big liar" just mean "tell lies in general and we don't know if the lies are small or big"
Or the words "little" and "big" are there for emphasis only and not actually tell us if the lie is small or big and "You big liar" is stronger "You little liar"?
The word "little" here is native colloquial English, in the UK at least, but this specific example is likely to be of, to, and between children, or in a child-like manner.
The little here, is to emphasise the offense perceived, and diminish the person it is addressed to. Similar phrases you might hear in arguments between adults - "You little bastard". "You little thieving shit". "She's a little cow". "You're the little snitch who told the police, aren't you?"
In all of these, "little" is used to belittle the person referenced, and emphasise the feelings of, and word used, by the speaker. It adds a feeling of distain and perhaps disgust or contempt, of the other person being weak, small or otherwise worth mocking and disregarding.
But perhaps because adults less often shout things like "you liar", that's more likely to be something said by, or related to, children, and therefore "You little liar" has a slightly childish petulant feeling that "You little bastard" (for.example) does not.
Update:
See also the Wikipedia article on intensifiers in swearing (AKA expletive attributives), which is almost exactly how 'little" is being used here - note the comment that "Words that are never thought of as offensive can be used in similar ways".
These would need to be understood in context.
"You little liar" sounds like something you might say to a child who lies, or someone who is childish. "You big liar" sounds like something you might say to someone who tells "big" lies.
Both sound colloquial and childish. It is extremely rare for adults to tell adults that they are liars in such a casual way. Calling someone a liar is an insult. So use only with caution.
It certainly depends on the context.
To my ears both "little liar" and "big liar" sound colloquial and familiar, things you'd say lovingly to your kids.
Not seriously to someone who's betrayed your trust. For that you'd use other adjectives like "dirty", "ugly" or even the f word. Maybe even without an adjective is stronger "You LIAR!"
I'd leave this as a comment but I don't have yet enough rep!
"You little liar" is in common usage. It is a compound insult, both calling the person little (e.g. petty) and also calling them a liar.
"You big liar" is not in common usage. It wouldn't be paired like that, because "big" is not such an insult.
"Big liar" is common; such as "Jim is a big liar". But it would not be paired with "you".
"Little" or "big" in that sentence applies to the "You" word in the sentence (the person you're addressing), not the "Lie" word in the sentence.
If these phrases are used between adults, it would be pretty likely that the adults are being playful or teasing. Adding "little" or "big" changes the tone from something more harsh as in saying "you liar," which I mostly hear only rarely and as more of a serious accusation.
As with much in the English language, it's entirely dependent on context and tone. I would say they are different but not actually in the difference between the definitions of 'little' and 'big'. Best illustrated with a few examples.
If my daughter said "Daddy, the mice ate all the chocolate biscuits again" with a naughty grin on her face, I might say either of those in reply with a grin and it'd be completely benign. Clearly she didn't intend me to believe what she said (that was a running joke between us when one of us had eaten something the other might have liked to have had some of).
In the benign case, the 'little' would be implying that it was a small lie and/or that she was in the habit of telling little lies, perhaps better known as 'fibs', 'little fibber' would be a better phrase as 'fib' implies a non-serious lie and makes it clear to the listener that you don't see this as a serious matter. The implication that she is in the habit of telling little lies itself is a benign one, and not meant to be taken seriously either.
In the benign case, the 'little' doesn't really refer to her being a child or physically small as one wouldn't change it in any way if saying it to one's spouse, for example.
If I said the same "You little liar" without the grin, and a more aggressive or even a fairly neutral tone she would immediately counter with "No Daddy, I didn't really mean it, I ate them, sorry" or similar (or just start crying I guess !), the point being that she would instantly know that I had mistaken her intent to make a joke which she didn't intend I take seriously, even though the words I said were exactly the same.
I would say that 'big' in a friendly context meant exactly the same, that it was a small lie, but British people commonly use 'small' to imply 'large' and vice-versa, it's all in the context and how it's said.
There is some element of familiarity (whether good or bad) implied by the use of either, "big liar" it's not generally a phrase an adult would use to another adult.
If said in reply to a work colleague saying "I didn't touch your wallet", when you just saw them putting it back in your jacket one might use either, but 'little' would be far more usual. In that case the 'little' would be a diminutive slight aimed at them. Not at their physical size or age, but purely as a demeaning slight.
Adding the 'little' in a negative sense is always about adding a barb to the statement, never about the lie being a small one.
One would be unlikely to say "You big liar" to a stranger, as it lacks impact and just sounds childish, it's not something you'd really say to seriously confront somebody whether you knew them or not. You'd simply say "You liar" if you were going to be terse about it or the rather more reserved British "I think you are lying", which might be said in an entirely level, calm manner but have more aplomb as a result.
The 'little' said to a woman doesn't make it specifically sexist as claimed above, it's demeaning to anybody regardless of their genetics when used in a negative context unless the definition of sexist means "Anything negative said to somebody of the opposite sex for any reason", which clearly it isn't.
In all cases, the implication of the big/little is found in the context of the exchange and the vocal inflection and any physical expressions when it is spoken.
I'm a mature well-read native English speaker with a classical education.
When do we say "You little liar" and "You big liar"?
Neither of these sounds to me like idiomatic English, although it could depend on the context.
"Little" and "big" in these sentences modify "liar." They don't describe the lies. They describe the person telling the lies.
"You big liar" sounds to me like something that an adult native speaker would never say. A child might say it, and if so, it would imply that the person lies a lot or their lies are particularly bad and shameful.
In "You little liar," "little" does not soften or reduce the accusation. It does the opposite.
If an adult man says to an adult woman, "you little liar," then it's an extremely sexist insult. "Little" means she's low in status compared to the man. It infantilizes the woman. The connotation would be very much the same if a woman said it to another woman.
If a man says "you little liar" to another man, then it's an extremely insulting and demeaning thing to say. The implication is that the man being addressed is not a real man. He's like a child, or a cockroach. But I don't think native speakers would actually say this. They would be more likely to say things like "you pathetic little cockroach," or "you disgusting little liar." Without the additional words, "you little liar" comes off more like a childish playground taunt, and it loses its impact.
Said in anger at someone who has seriously deceived you, "You little liar!" is not at all childish. It calls them a liar, but also shows contempt for them by the use of "little", which here can mean "petty" or "insignificant".
I would say "You big liar" is more likely to be used playfully towards children, or casually with friends, but it too could be used in anger or frustration, roughly meaning "That's nonsense!", or "You're full of shit!", or other similar phrases with stronger words.
My context is that of a native English speaker in Alberta, Canada.
"Little liar " applies the "little" to the person telling the lie. Usually a child or person of much reduced social status to the recipient.
"Big liar" applies the "big" to the nature of the lie. The lie is an exaggeration, or an outrageous claim.
Neither of these are hard rules, just the most common usage.
For example, "big liar" could also be directed at a physically large person bullying a small person, with the "big" applying to the liar's physique, not the nature of the lie.
If you want to refer to the lie itself as being greater, then you would say "you tell big lies". In this context "big" can only refer to the lies, not the person.
"You little liar" and "you big liar" are diminutives and/or familiars. They are also an example of the simplified usage that is typically reserved for children, akin to "baby-talk". While the meaning intended can somewhat echo the definitions for "little" and "big", the real point is to diminish, insult, or offend the person who is the point of the remark.
They could be used for rough humor amongst close associates, or associates who have a known (and sufficient) sense of humor to realize the remark was intended as rough (cutting) humor. This would require knowing your audience, or having sufficient confidence in your presentational abilities that you could be confident the audience would realize the remark was intended humorously. This sort of humor is a form of sarcasm.
One could use these, or witness them used, when there is a situation with extreme social differentiation. E.g. An adult addressing a child, or one of a high social class addressing someone they thought to be a lower social class. Using them then would be akin to saying: "I am your superior" and the assumption would be that the accusation of lying should be taken as true. In that case, it is a diminutive, intended to belittle and apply guilt to the accused.
Children, unaware of more sophisticated usage, might use either form. In one aspect - they might use it untruthfully, to insult and diminish the object person. Or, in the case where a lie was observed, it would be used accusatorily, to assign guilt to the object person. In both cases, the usage is diminutive, i.e. meant to diminish the status of the person who is the object of the comment.
As for using "little" or "big" in the phrase, the difference is essentially meaningless, even though the inferences are derived from essentially different definitions. In the case of "a little liar", "little" refers to the personage being addressed. As such, it is an insult or a diminutive - diminishing the status of the addressed. In the case of "a big liar", the reference is to the size, or frequency, of the lies, indicating that the lie is "a whopper", or that the addressed personage lies frequently. These usages are not logically, or grammatically, consistent. Without doing further research into the usage, I will say I think they are idiomatic, non-literal usage. Both usages are intended to accuse and apply guilt to the object person.
In closing, I would not recommend this usage for an ELL. By the time you are familiar enough with your associates, or your audience, to accurately and effectively use these phrases in a social setting, you will be well past "native-speaker" level. As humor, they are of the "cutting" variety, as banter, or sarcasm. Such usage requires a good level of recognition of verbal nuance, body language, and social skills, unless one does not mind socially awkward situations, or if one truly intends to give insult. If one intended to give insult, be aware that such usage risks extreme reactions.
Both “big liar” and “little liar” are describing the person and not what they said. Some good examples are the book titles My Brother is a Big Fat Liar and God is a Big Fat Liar, which are humorous books about a child getting angry at someone. Pretty Little Liars is a book that is literally about attractive teenage girls who’ve told serious lies, whom we’re meant to sympathize with because of their immaturity and powerlessness—the two senses in which they’re “little.”
Another adjective that’s often used with phrases like this is “big old” or “little old.” These emphasize how insignificant and harmless someone is. In context, it can be affectionate, or insulting.
In contrast, a “little white lie” is small and benign, or a “petty lie” is one about something inconsequential, with the implication that only a compulsive liar would say something like that. The phrase “minor lie” is more neutral. If you talk about your political opponents’ “Big Lie,” you’re comparing them to the Nazi propaganda minister, Joseph Goebbels.
It's a friendly riposte to someone who speaks a probable untruth. It's not meant to be an insult.
I'm surprised that none of the answers so far give the source of this phrase: the poem Matilda, which is a precautionary tale for children, warning against lying, dating from the early part of the twentieth century when such tales were in vogue . Since it is still under copyright I shan't reproduce it in full here, but it can be found online. Matilda is essentially a retelling of Aesop's The Boy Who Cried Wolf in which a young girl claims her house is burning down before eventually dying in a real blaze. When the real fire occurs, the poem includes this pair of lines:
For every time She shouted ‘Fire!’
They only answered ‘Little Liar’!
From which the phrase "Little Liar" entered common English usage. Although originally it referred to a child with a poor regard to truth, it is today most often used dismissively to refer to an adult who lies like a child and should know better.
