What is the singular possessive word for glass?

Answer 1

The possessive singular of all English nouns, regardless of spelling, is formed by the addition of -'s: glass's. Possessive singulars are pronounced as if they were simple plurals in -s, so that glass's is pronounced exactly like glasses.

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Many people will add 's to words that end in -s, it is not always correct and never correct for words ending in -ss. The general rule is that only an apostrophe is added to words ending in -s, -z or -x. Again, for plural words ending in -s just add the apostrophe.

-'s is normally only added to words that end in -s where the -s is silent, e.g.

Arkansas's new Governor; Illinois's former Governor; the Marine Corps's policy.

Answer 2

All English nouns ( with the possible exception of the names Jesus and Moses) form the possessive singular by adding 's: glass's

Answer 3

glass's