Of

[uhv, ov; unstressed uh v or, esp. before consonants, uh] /ʌv, ɒv; unstressed əv or, esp. before consonants, ə/

preposition
1.
(used to indicate distance or direction from, separation, deprivation, etc.):
within a mile of the church; south of Omaha; to be robbed of one’s money.
2.
(used to indicate derivation, origin, or source):
a man of good family; the plays of Shakespeare; a piece of cake.
3.
(used to indicate cause, motive, occasion, or reason):
to die of hunger.
4.
(used to indicate material, component parts, substance, or contents):
a dress of silk; an apartment of three rooms; a book of poems; a package of cheese.
5.
(used to indicate apposition or identity):
Is that idiot of a salesman calling again?
6.
(used to indicate specific identity or a particular item within a category):
the city of Chicago; thoughts of love.
7.
(used to indicate possession, connection, or association):
the king of France; the property of the church.
8.
(used to indicate inclusion in a number, class, or whole):
one of us.
9.
(used to indicate the objective relation, the object of the action noted by the preceding noun or the application of a verb or adjective):
the ringing of bells; He writes her of home; I’m tired of working.
10.
(used to indicate reference or respect):
There is talk of peace.
11.
(used to indicate qualities or attributes):
an ambassador of remarkable tact.
12.
(used to indicate a specified time):
They arrived of an evening.
13.
Chiefly Northern U.S. before the hour of; until:
twenty minutes of five.
14.
on the part of:
It was very mean of you to laugh at me.
15.
in respect to:
fleet of foot.
16.
set aside for or devoted to:
a minute of prayer.
17.
Archaic. by:
consumed of worms.
[uh v] /əv/
auxiliary verb, Pronunciation Spelling.
1.
have:
He should of asked me first.
1.
Old French.
1.
variant of (by assimilation) before f: offend.
/ɒv; unstressed əv/
preposition
1.
used with a verbal noun or gerund to link it with a following noun that is either the subject or the object of the verb embedded in the gerund: the breathing of a fine swimmer (subject), the breathing of clean air (object)
2.
used to indicate possession, origin, or association: the house of my sister, to die of hunger
3.
used after words or phrases expressing quantities: a pint of milk
4.
constituted by, containing, or characterized by: a family of idiots, a rod of iron, a man of some depth
5.
used to indicate separation, as in time or space: within a mile of the town, within ten minutes of the beginning of the concert
6.
used to mark apposition: the city of Naples, a speech on the subject of archaeology
7.
about; concerning: speak to me of love
8.
used in passive constructions to indicate the agent: he was beloved of all
9.
(informal) used to indicate a day or part of a period of time when some activity habitually occurs: I go to the pub of an evening
10.
(US) before the hour of: a quarter of nine
abbreviation
1.
Old French (language)
prep.

Old English of, unstressed form of æf (prep., adv.) “away, away from,” from Proto-Germanic *af (cf. Old Norse af, Old Frisian af, of “of,” Dutch af “off, down,” German ab “off, from, down”), from PIE *apo- “off, away” (see apo-). Primary sense in Old English still was “away,” but shifted in Middle English with use of the word to translate Latin de, ex, and especially Old French de, which had come to be the substitute for the genitive case. “Of shares with another word of the same length, as, the evil glory of being accessory to more crimes against grammar than any other.” [Fowler]

Also from 1837 a non-standard or dialectal representation of have as pronounced in unstressed positions (could of, must of, etc.)

assimilated form of ob- before -f-.

verb

Have •In verb constructions, used for humorous or dialect effect: I must of gone crazy or something (1844+)
1.
Oriental female
2.
outfield
3.
outfielder