niffy 

Slang for notification on the social-networking site Facebook.

Oh you commented? Facebook didn't give me a niffy!

niffy by ZakkyChan December 10, 2010

Niffy 

A girl living a double life

How mysterious Niffy can be

Niffy by Nymphadora Tonks July 17, 2018

niffy 

Resembling the characteristics of today's most debonaire gentlemen. Similar to player or pimp.

That was pretty niffy.
Way niffier than Brad Pitt or Johnny Depp.

niffy by Jasmine Morris June 5, 2005

niffy 

British for malodorous.

I was stuck in a lift with a niffy bird.

niffy by G-e September 27, 2005

Niffy Zasus

A person who has uncontrollable body odour in the arm pit area, so potent that you can smell them before they have even entered a room, most commonly found in gyms, chaz zones and university common rooms. Named after early a Hollywood star Zasu Pitts.

Jeez, I was on the treadmill this morning and the dude on the machine net to me had really niffy Zasus. It was so bad, he should have carried a biohazard warning.

Niffy Zasus by Gryph73 January 11, 2021

a nifty

A fifty. Cockney rhyming slang for £50

"How much to heathrow mate."

"bout a nifty mate"

a nifty by skatatoulas April 7, 2012

Niffo 

A Dutch word for 'bro'. Usually used as slang.

Denel: "Huts à niffo alles fakka wakka met die skorro brokko?"
Mathieu: "Nee kanker op à zemmel"

Niffo by Yeeeeeesh June 7, 2020