Are possessive apostrophes legal in Codenames? For example, "women's 3" for "health"
If it's one English word and it's a clue about the meaning(s) of the word(s) on the table (and it isn't a form of any words on the table, etc.), then it's a valid clue, yes. Apostrophes are not prohibited.
(Not rule to cite; it is difficult to prove a negative).
For the question of &quot;women's&quot; vs. &quot;woman's&quot;, etc., you are free to spell it out so as to disambiguate the clue (and should if asked) .

You are allowed to spell out your clue.


You should spell out your clue if someone asks.