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”).
1
Enclitic, Morpheme A possessive marker, indicating that an object belongs to the noun or noun phrase bearing the marker.
Jane's house is bigger than Sarah's.
The cat bit the dog's tail. (the dog + 's)
3 more examples
The cat bit the dog with the shaggy fur's tail. (the dog with the shaggy fur + 's)
women's contributions to science
Before kick-off, a section of Chelsea's support sadly let themselves and their club down by noisily interrupting the silence held in memory of the Hillsborough disaster and for Livorno midfielder Piermario Morosini, who collapsed and died after suffering a heart attack during a Serie B game on Saturday.2012 April 15, Phil McNulty, “Tottenham 1-5 Chelsea”, in BBC:
2
Enclitic, Morpheme In the absence of a specified object, used to indicate “the house/place/establishment of”.
We'll arrive at Jose and María's in time for dinner.
I'm going to the butcher's for a steak.
2 more examples
I bought it at Tesco's. (see s-form)
greengrocer's
3
Enclitic, Morpheme Indicates a purpose or a user.
You need a driver's license.
Alex can be a girl's name.
2 more examples
That's a girl's toy. (A toy intended for use by girls.) — Homographic to: That's a girl's toy. (The toy of a specific girl.)
people's
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Enclitic, Morpheme Used to indicate a quantity of something, especially of time.
I took three weeks' holiday.
The rocks lay at about a mile's distance from the shore.
5
Enclitic, Morpheme Used to indicate various other kinds of relationship, such as source or origin, object of an action, subject depicted, etc.
She got angry at my niece's trying to lie to us.
the doctor's help (help provided by the doctor)
4 more examples
the King's capture (event of the King being captured)
my father's portrait (portrait depicting my father)
in Dublin's fair city (in the fair city of Dublin)
JFK Airport is among America's busiest.
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Enclitic, Morpheme Attached to a noun or noun phrase linked to a genitive of, forming a double genitive (Compare of mine, etc.)
a friend of Sarah's
Have you heard this new idea of our boss's?
1 more example
NAy, but this dotage of our Generals Ore-flowes the meaſure: […]c. 1606–1607 (date written), William Shakespeare, “The Tragedie of Anthonie and Cleopatra”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, →OCLC, [Act I, scene i], page 340, column 1:
Etymology Equivalent to -s, with addition of apostrophe.
1
Enclitic, Morpheme, Proscribed, Sometimes 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.
There are four 3’s in my phone number.
“Banana” has three a’s and one b. (apostrophe "s" used so that the plural of “a” is not confused with the word “as”)
3 more examples
You can buy CD’s in that shop.
These are the do’s and don’ts. (apostrophe "s" used as “dos” may be misread)
10’s; 100’s; A+’s; A.U.’s; don’t’s; s’s
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Enclitic, Morpheme, Obsolete Used to form plurals of foreign words, to clarify pronunciation, such as “banana’s” or “pasta’s”.
index’s
3
Enclitic, Morpheme, Proscribed Used to form the plural of nouns that correctly take just an "s" in the plural. See greengrocer’s apostrophe.