an ending used in writing to represent the possessive morpheme after most singular nouns, some plural nouns, esp. those not ending in a letter or combination of letters representing an s or z sound, noun phrases, and noun substitutes, as in man's, women's, baby's, James's, witness's, (or witness'), king of England's, or anyone's.
an ending marking nouns as plural (boys; wolves), occurring also on nouns that have no singular (dregs; entrails; pants; scissors), or on nouns that have a singular with a different meaning (clothes; glasses; manners; thanks). The pluralizing value of is weakened or lost in a number of nouns that now often take singular agreement, as the names of games (billiards; checkers; tiddlywinks) and of diseases (measles; mumps; pox; rickets); the latter use has been extended to create informal names for a variety of involuntary conditions, physical or mental (collywobbles; d.t.'s; giggles; hots; willies). A parallel set of formations, where has no plural value, are adjectives denoting socially unacceptable or inconvenient states (bananas; bonkers; crackers; nuts; preggers; starkers); cf.