Meaning of -'S in English

-'S

transcription, транскрипция: [ s after vȯiceless consonants other than ]

s, sh, ch; z after vowels and vȯiced consonants other than z, zh, j; əz after s, sh, ch, z, zh, j noun suffix or pronoun suffix

Etymology: Middle English -es, -s, genitive singular ending, from Old English -es; akin to Old High German -es, genitive singular ending, Greek -oio, -ou, Sanskrit -asya

— used to form the possessive of singular nouns

boy 's

of plural nouns not ending in s

children 's

of some pronouns

anyone 's

and of word groups functioning as nouns

the man in the corner 's hat

or pronouns

someone else 's

Merriam-Webster's Collegiate English vocabulary.      Энциклопедический словарь английского языка Merriam Webster.