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1.
A word meaning extraordinary hatred and meaness. If you were to use the word Ranny, you may either become evil or develop a extreme liking of cookies. use this word wisely
When i saw the abusive relationship, I knew that girl had an extreme case of Ranny.
by Queen Bloristuter May 03, 2008
 
2.
I believe I heard some charver scumbag or other use this word to mean 'hungry'. Possibly derived from 'ravenous'. As in:
Eee, ah feel puar ranny th'knaas. Let's howay doon the lurcal Greggs!
by Bonny lad November 11, 2004
 
3.
Its a common insult. It got inspired by a scrub (see Scrub) who have faucking life.
Chy: wow dude!! THAT WAS MINE!! gimme my watherghost's drop!
HNT: OMFG gtfo ranny!
by Marco Lapp December 18, 2005