I. -'s¹ /z, s/

1. the short form of ‘is’:
John’s here.
What’s that?
She’s writing a letter.

2. the short form of ‘has’:
Polly’s gone out.
A spider’s got eight legs.

3. a short form of ‘us’ used only in ‘let’s’

4. spoken a short form of ‘does’, used in questions after ‘who’,‘what’ etc that many people think is incorrect:
How’s he plan to do that?

[TahlilGaran] Dictionary of Contemporary English ▲

II. -'s² suffix

1. forms the possessive of singular nouns, and of plural nouns that do not end in -s:
my sister’s husband
Mary’s generosity
yesterday’s lesson
the children’s bedroom

2. British English the shop or home of someone:
I bought it at the baker’s (=at the baker’s shop).
I met him at Mary’s (=at Mary’s house).

[TahlilGaran] Dictionary of Contemporary English ▲

-s /z, s/ suffix

1. forms the plural of nouns:
a cat and two dogs

2. forms the third person singular of the present tense of most verbs:
he plays
she sits

[TahlilGaran] Dictionary of Contemporary English ▲

-s’ /z, s/ suffix
forms the plural possessive of most nouns:
the girls’ dresses
the islands’ inhabitants

[TahlilGaran] Dictionary of Contemporary English ▲

I. S¹ , s /es/ noun (plural S’s, s’s) [uncountable and countable]
the 19th letter of the English alphabet

[TahlilGaran] Dictionary of Contemporary English ▲

II. S²

1. the written abbreviation of south or southern

2. the written abbreviation of small, used on clothes to show the size

[TahlilGaran] Dictionary of Contemporary English ▲

S
Second(s) 
Smile 
South 
Spades (playing cards)

[TahlilGaran] Acronyms and Abbreviations Dictionary ▲