Part of the mank-jank-skank-rank-gank scale of just how bad something is. All are negative terms.
gank is worse than
rank is worse than
skank is worse than
jank is worse than
That dead horse in your garden is rank
something horrible, discusting, sick.
Guy1: I smell my socks.
Guy2: Arhh mate thats rank.
Something/someone poor, gross, ugly, "ew".
The blanket on Roseanne's couch is rank.
something which is 'rank' is disgusting - for example it may be used with reference to food or smells or mental images.
'aw, man, that's rank'
something that smells horribly bad, or disgusting
farts are rank
Maxime's underwear is fucking rank
A complimentary opinion, as in, "it ranks highly", though the adverb (such as "highly") is deliberately left out. Used mostly when lauding a visual or musical work of art.
"The Beatles' 'Rubber Soul' ranks."
"'Star Wars' ranks."
"His guitar-playing ranks."
to make fun of; to diss someone for no particular reason
oh, you got ranked on.