I know that both the words are pronounced and used differently. I also found another question on this site: "Use of loose and lose [closed]", but that is about the usage of the word. My question is completely different to that one.

The ending 'se' is pronounced 's' in loose and 'z' in lose: respectively, /luːs/ and /luːz/. What caused this change?

3 Answers 3



'Lose' came from Old English (OE) word losian while 'loose' was taken from Old Norse around the thirteenth century. There was a process in OE through which s, f and th became voiced respectively to [z], [v] and [ð] when they occurred between voiced sounds i.e. between two vowels or a vowel and anther voiced sound. There was no phonemic contrast of voice among the OE fricatives.

The ⟨s⟩1 in the OE form of 'lose' was intervocalic (between vowels), so it became [z] which survived into Modern English (ModE).

'Loose' came into English in the thirteenth century by the time the voicing was no longer productive, so it retained the original [s] sound.


There are lots of pairs that exhibit the same sound change such as wolf/wolves, bath/bathe, house (n)/house (v), breath/breathe, life/lives, loaf/loaves, close (adj)/close (v), knife/knives, cloth/clothes etc. All these are the remnants of OE property called intervocalic fricative voicing

Fricative voicing

Old English had a phonetic property called fricative voicing, whereby non-velar fricatives—s, þ ~ ð2, f—became voiced when they were flanked by vowels, or a vowel and another voiced consonant. The fricatives s, þ ~ ð, f were voiceless elsewhere. /ʃ/ was always voiced.

There were no distinctive voiced fricatives in Old English. The realisations [f - v], [θ - ð] and [s - z]3 were allophonic. It was the only way to get [z], [v] and [ð] because Old English didn't have phonemic [z], [v] and [ð]. In a nutshell:

  • [f] and [v] were the allophones of the phoneme /f/
  • [s] and [z] were the allophones of the phoneme /s/
  • [θ] and [ð] were the allophones of the phoneme /θ/


  • Wolf was wulf and it would've been pronounced [wulf], wolves was wulfas and would've been pronounced [wulvɑs].
  • House (noun) was hūs and would've been pronounced [huːs], house (verb) was hūsian and would've been pronounced something like [huːziɑn].
  • Bath (noun) was bæþ and pronounced [bæθ], bathe was baþian and would have been pronounced [ˈbɑ.ði.ɑn].
  • Close (verb) was clȳsan and would've been phonetically [ˈklyː.zɑn], close (adj) was clȳs, and would've been [klyːs].

Note that the fricatives were phonemically voiceless; the voicing was allophonic.

Lose vs loose

Lose came from Old English losian. The s was intervocalic, so it became [z] due to that property:

  • losian → [ˈlo.zi.ɑn]

In Middle English, it became losen ([ˈloːzən]), then it lost the terminal nasal and became [ˈloːzə], then the terminal schwa was lost and the vowel [oː] was changed to [uː] by the Great Vowel Shift.

Loose entered English in the 13th century and by that time, the voicing wasn't productive anymore. So it retained its original /s/.


  1. I use ⟨angled brackets⟩ for orthography/spelling.
  2. þ (thorn) and ð (eth) were used interchangeably by OE scribes to represent the th sounds. Do not confuse ð with IPA [ð].
  3. [Square brackets] are for allophones/contextual variants.
  • 3
    I had no idea wolf/ wolves underwent the same process. I have always wondered about that.
    – user128441
    Commented Jan 19, 2021 at 13:07
  • 2
    @MackJad: In modern English, this dynamic is apparent in the way that these noun or adjective + verb pairings generally have voicing on the verb, and no voicing on the noun or adjective. Compare also breath and breathe, swath and swathe, life and live, strife and strive, cleft and cleave, heft and heave, weft and weave. Commented Jan 19, 2021 at 18:28
  • 2
    Oddly, while I can think of other examples of other words with "-oose" (moose, goose, caboose), I know of no other example of a word spelled with "-ose" that's pronounced that way. They're all pronounced with a long 'o' instead either with an 's' sound (dose, close (adj.), morose, comatose) or a 'z' sound (rose, chose, close (v.), dispose). One word that is pronounced like "lose" but spelled like "loose" is "choose". English is just weird. Commented Jan 19, 2021 at 20:15
  • 4
    @DarrelHoffman: "I know of no other example of a word spelled with "-ose" that's pronounced [to rhyme with lose]." How about whose. :) Commented Jan 20, 2021 at 1:06
  • 1
    @DarrelHoffman: I read somewhere that the /uː/ in lose is by analogy with loose. It should've been */əʊ/ (vowel in 'no') but it isn't.
    – Void
    Commented Jan 20, 2021 at 14:04

"Loose" has probably always been pronounced with [s] - the Norse word that it was borrowed from is spelt with double "s".

"Lose" has been pronounced with [z] at least since Old English. (Between vowels, OE "s" was pronounced [z]. I use square brackets here because the s/z distinction in OE wasn't phonemically significant - they were allophones.)

The words "loose" and "lose" are etymologically only very distantly related: they derive from different Germanic roots (but probably have a common origin in Proto-Indo-European).

You should not expect to see a close or consistent sound/spelling relationship in English.

  • 2
    – Void
    Commented Jan 19, 2021 at 9:58
  • Yes. As in all questions of this sort, they're different words, and so are pronounced differently (depending on one's local accent, of course). Spelling came later, and is only approximately phonetic.
    – jamesqf
    Commented Jan 20, 2021 at 2:41

They are different words spelled differently with different meanings. Hence they are pronounced differently.

  • 1
    Unfortunately your reasoning is not correct. In fact English has a lot of homophones—words with different meanings (and possibly spellings), that are pronounced exactly the same.
    – bodo
    Commented Jan 20, 2021 at 14:47
  • I'll give this a +1 because while the linguistic stuff is interesting, is not really a surprise that two words with different spellings and meanings are not pronounced the same
    – eps
    Commented Jan 20, 2021 at 15:21
  • @bodo And on top of that, homographs that are not pronounced the same ("close", "house", etc. as in the current top answer here)!
    – Joe
    Commented Jan 20, 2021 at 15:45
  • Some very common ones are: "you're"/"your", "there"/"their"/"they're", "than"/"then", "affect"/"effect", "were"/"where"/"we're", "whose"/"who's", "alot"/"allot"/"a lot", and "definitely"/"definately" (some are regional. And other reasons.) Commented Jan 21, 2021 at 5:23

You must log in to answer this question.