Mating is the term used for sexual activity, mostly for animals. Is there anything wrong with mate?
My mate could mean my sexual partner, but I've heard that in less obvious contexts, such as someone was talking about his roommate (a man), himself being declared heterosexual. I was a bit embarrassed by this word, but I haven't asked.
So, does mate always imply at least a bit of sexual context?
Think of mate as related to pair. A pair is composed of two things that belong together, each thing in the pair is a mate. So the short answer to your question is no. To elaborate:
One of my socks has gone missing, I'm looking for its mate.
When you find the missing sock, you complete the pair; the sock you couldn't find is the mate to the sock you already had.
The two lions faced each other on the savannah, fighting over their potential mate.
In this case the two male lions are fighting over a female lion, and whoever wins will be their mate--this is as you mentioned in your question, where a mate is the second half of a sexual pair. (This can also be applied to humans and be grammatically correct, but it will sound odd.)
Penguins mate for life.
Animals again, and obviously there's a sexual element there, but this is about the pairing of the two as well. They're going to stay together as partners for life.
John Smith was the pirate captain's first mate.
As StoneyB commented, mate can also be used to describe officers on ships. The first mate is the captain's right-hand man.
Good day, mate!
As others have mentioned, mate is also Austrailian slang used to refer to a friend.
So as you can see, there are many different contexts in which mate has different meanings!
No, not at all. In fact, the word mate is quite often used in colloquial Australian and British English.
G'day Mate (Good day Mate)
Being one of the phrases quite often associated with Australia.
Mate in this context means "friend" or "buddy", and is not gender specific (used by both men and women to refer to men and women)
Some other usages, that are fairly common:
A mate of mine went to Sydney last week.
Are you alright, mate?
What time are your mates arriving?
In my experience, mate as used to describe another human being essentially never refers to any kind of sexual activity or sexual partner. Mate means different things, depending on the locale and dialect, for instance:
G'day Mate
'lright, mate?
Uses the word mate to mean singular you in many dialects of English, particularly Australian English and Cockney and Northern British English.
Now look here, mate
Is an intensified aggressive form of the word "you" in some dialects of British English
Me and my mates are going to go out later for drinks
What time are your mates going to get here?
Is an informal meaning of "friends", in many dialects of English, but particularly as spoken in Northern England.
Mate is also an older English title, meaning "member" or "partner" (in a non-sexual context), and this holds over in many seafaring and military contexts:
Capitan Silver, this is First Mate Johnny Williams.
In this context, mate and first mate are naval titles. You'll sometimes see this as well in the "Pirate Vernacular":
Ahoy there, mateys!
In this case, "mateys" is an old fashioned (and no longer grammatical) plural of mate, and is an address to the crew. It does not imply that the crew are either friends or sexual partners of the captain.
Finally, it is important to note that mate almost always does have a sexual context whenever the discussion is specifically about non-human animals. In this case it can be either a verb or a noun.
We're flying in Kanga to Sydney zoo to mate with Zippy the Kangaroo who lives there.
Penguins mate for life
Liara, the lioness at London Zoo is the mate of Rory the Lion
As we can see, the peacock spreads its tail features to attract a mate.
Do not use the word "mate" meaning a sexual partner in the context of another human being outside of the context of academic medical research. Doing so is very insulting, because it suggests that the partner is almost in-human, and suggests a coldness or clinicalness to the activity that your listeners would likely find uncomfortable.
In British English, you could say "See you then, mate." without implying anything sexual; it is just an informal form of address between men, or boys.
It is also informally used to mean friend, as in "I was with a mate." In plumber's mate, mate means assistant.
I agree with Deco, with the added caveat that in Australian English mate can sometimes be used to express anger or aggression. "Listen here mate..." or "look mate..." are often used to begin making a forceful point, or to tell someone to back off.
Furthermore, calling a stranger mate can in certain circumstances get a negative response, as some people don't like strangers being casual with them.
Only a skilled speaker should attempt to use this word on a stranger.
Like most British sayings it is derived from its Naval history. "Ship mates" Americans say 'buddy'or 'dude' Spanish say 'amigo' Russians say 'droog' etc. British/Australians/New Zealanders say 'mate'. Nobody will take offence :)
To me mate is the equivalent of brother or someone I am especially close to. I use the term me mate, exclusively for an individual who I love hanging with and just enjoy their company. The bond I share with me mate is mutual. The term is very endearing to me, and in me life time I have only used the term twice. For me to use me mate the bond may at times be physical but that is a timed element.
