There are some places where men and women are segregated — for example public toilets and public swimming pool changing areas.

By this I mean, for example, that there are "Men's toilets" and "Ladies' toilets".

However, in some more cosmopolitan swimming baths, and other places, there are such things as unisex changing areas, or unisex toilets.

From my understanding uni- implies one, as in universe, unilateral or unicycle.

However when it comes to unisex, this means both sexes, so applies to two things.

How does uni- mean one in unisex? Does it mean one?

  • 5
    A more proper Latinism would be ambisex ("both sexes"), but of course if you say that no one will know what you're talking about. Commented Aug 9, 2011 at 12:16
  • Similarly - I always wondered why co-ed meant women instead of men+women
    – mgb
    Commented Aug 9, 2011 at 15:19
  • 5
    @Martin Many colleges and universities used to have exclusively male students. When that changed and women were admitted, the institutions became "co-educational." The women were referred to as "co-educational students" or "co-eds" and although technically this could apply to the men as well, it was associated with the women because their presence made the institution mixed-sex.
    – Kit Z. Fox
    Commented Aug 9, 2011 at 18:00

2 Answers 2


From the Oxford dictionary online, via Wikipedia:

The combining form uni- does normally mean 'one, having or consisting of one': it comes from Latin unus 'one'. It forms words such as unicycle, a term for a cycle with just one wheel, and unicellular, meaning 'consisting of a single cell'. And in fact the 20-volume historical Oxford English Dictionary contains entries for the words unisexual, meaning 'of one sex or relating to one sex' and unisexuality, meaning 'the state of being unisexual'. Both these words date back to the early 19th century.

Unisex is a much newer word: it was coined in the 1960s and originally used in relatively informal contexts. Its formation seems to have been influenced by words such as union, united, and universal, from which it took the sense of something that was shared. So unisex can be understood as referring to one thing (such as a clothing style or hairstyle) that is shared by both sexes.


Unisex unequivocally represents single sex, distinct from bisex. The word uni represents one, which is altogether different from bi, which represents both. The word union also represents one and it does not represent its constituents. In common parlance, uni is understood as one. Giving a different meaning to uni as "more than one" is tantamount to doing violence to the word bi, which stands for two; i.e. "more than one".

It appears that unisex virtually means single gender and bisex represents both genders. There is no history or vision behind using the word unisexual for both genders either commonly or separately.

If the proper expression bisex unit is used and displayed, the person entering will be aware of the consequences, yet such may call for the services of unisex or single gender.


Not the answer you're looking for? Browse other questions tagged or ask your own question.