O.N.I.F.C. 

Wiz Khalifa's second album.

Only

Nigga

In

First
Class

Only.Nigga.In.First.Class
O.N.I.F.C.

O.N.I.F.C. by @Mig_e_ January 30, 2012

O.N.I.T 

a "code"(spell it out so the tweaker dont know your talking bout them ) term to describe when someone appears or seems to be all skitzed out........the good shit!

seeing the 7 eleven clerk twitch and pucker lips trying and really beliving she was sexy made him say, "damn, she is O.N.I.T!

O.N.I.T by The one and only BK August 26, 2012

O.N.S. 

One night stand

Anyone down for a O.N.S.

O.N.S. by Rashad843 January 20, 2017

O.N.I.C 

Only nigga in charge. Typically refers to a person several steps above an alpha and even higher than a H.N.I.C (Head Nigga In Charge).

Gurren is the O.N.I.C in Seraph of the end.

O.N.I.C by Booligan123 November 4, 2018

O.N.T.

ontOne Night Type (girl, coz guys are all like that).

<Girl1> last night I had some fun with that dude I met at *** <wink>.
<Girl2> cool, I didn't know you were O.N.T., you go girl,......

O.N.T. by none2 December 16, 2005

O.N.I.M. 

An acronym standing for "Oh No, It's Monday".

Used to express the discontentment and dread one feels for Monday, the beginning of another tedious week.

Tito: "YES! let's get this weekend started!"
Todd: "You idiot, you've been passed out for 3 days."
Tito: "wait, what? O.N.I.M.!"

O.N.I.M. by ABDICKOX November 19, 2010

O.N.E.

An acronym for Omaha, Nebraska.

Yeah dude, I'm from the O.N.E.

O.N.E. by Frazzy-B January 13, 2005