No, the word sharpness is a common, abstract, uncountable noun, a word for the quality of a thing.
I can't think of a use for the noun sharpness in the possessive form; I don't know what the quality of sharpness could posses. If there is a use for the possessive form, that would be: sharpness's.
the possessive form of the plural noun comments is comments'.Example: His comments' sharpness took the lady by surprise.
The noun form of the adjective "sharp" is "sharpness." In grammar, when an adjective is used to describe a quality or characteristic of a noun, the noun form is often created by adding the suffix "-ness." In this case, "sharpness" refers to the quality of being sharp.
The possessive singular noun is explorer's. The possessive plural noun is explorers'.
The possessive form for the noun coyote is coyote's.
The possessive form of zoo is zoo's.
The possessive form for the noun preacher is preacher's.
The possessive form for the noun laboratory is laboratory's.
No, he is not possessive. The possessive form would be his.
The possessive form for the noun oxygen is oxygen's.
The possessive form is grandson's.
The possessive form is island's.
The possessive form for the noun coyote is coyote's.