The noun quantum is the singular form; the plural is quanta.
pants, trouser, scissors, tweezers
if you mean the word "word" than singular: wordPlural: wordsif you are wondering what the singular and plural forms are, then singular is one (like cat) and plural is two or more (like cats)
singular- vegetableplural- vegerablesi am 99.99999% sure. but feel free to alobrate if i am wrong
Pants, Trousers