Of a person who has a very difficult personality; a perfectionist.(adjective)
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Use "hard-assed" in a sentence
"I especially liked Hans Brauer (Darby on Sons of Anarchy) as the supposedly hard-assed covert agent who folded like a little kid once he discovered This is Not a Game."
"Back to Sherrie & Ellen: "When you do The Rules, he treats you like a fragile, delicate flower" -- even if you're a hard-assed CEO to the rest of the world!"
"Her back straightened, her fingers tightened on the shotgun, and once again, I saw a glimmer of the hard-assed vampire that I remembered."