To have an out-of-proportion vindictiveness toward someone or out-of-proportion desire to crush someone (metaphorically or literally). The person with the out-of-proportion feeling or the person on the receiving end of the feeling is usually male, but not necessarily so. Generally used with the preposition for.
God, Mark has a real hard-on for Eddie after Eddie got promoted over him.

That bitch, Katy, has a hard-on for Esther because she stole Katy's guy.
by dockrrrk October 19, 2012
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cool, really outstanding, look nice.
Them shoes go hard. Your hair go hard.
by Cam April 8, 2003
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"Last party we went to had a bunch of bitch-beers and no hard A."
by shackledxdollie November 21, 2004
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He hasn’t been the same after he started smoking hard.
by dadondadda December 23, 2018
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Anything meaning good, like tight, cool, ill, etc.
"Yo that song is hard."
by Kerrry November 1, 2007
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