-'s

Meanings

1. A possessive marker, indicating that an object belongs to the noun or noun phrase bearing the marker.
2. In the absence of a specified object, used to indicate “the house/place/establishment of”.
3. Indicates a purpose or a user.
4. Used to indicate a quantity of something, especially of time.
5. Used to indicate various other kinds of relationship, such as source or origin, object of an action, subject depicted, etc.
6. Attached to a noun or noun phrase linked to a genitive of, forming a double genitive (Compare of mine, etc.)

1. Used to form the plurals of numerals, letters, some abbreviations and some nouns, usually because the omission of an apostrophe would make the meaning unclear or ambiguous.
2. Used to form plurals of foreign words, to clarify pronunciation, such as “banana’s” or “pasta’s”.
3. Used to form the plural of nouns that correctly take just an "s" in the plural. See greengrocer’s apostrophe.

1. Alternative form of -'s.

Etymology

From Middle English -s, -es, from Old English -es (“-'s”, masculine and neuter genitive singular ending), from Proto-Germanic *-as, *-is (masculine and neuter genitive singular ending). The apostrophe was added under the false belief that it was a contraction of English his, and retained to distinguish it from the plural. Cognate with Dutch -s, -es (“-'s”), German -s, -es (“-'s”), Danish -s, -es (“-'s”), Swedish -s (“-'s”), Norwegian -s (“-'s”), Icelandic -s (“-'s”).