Having a wicked, malignant disposition; morally bad.(adjective)
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Use "black-hearted" in a sentence
"First, there's the show's black-hearted secret weapon, Tyler (Ashton Holmes), whose tangled relationship with Nolan is exposed; and now that the saucy Amanda (Margarita Levieva) — aka the actual "Emily Thorne" — is here to stay, with her claws into the unsuspecting Jack Porter (Nick Wechsler), she's bound to be making more waves in these Hamptons waters."
"Lo, they did not anticipate such a black-hearted child such as I."
"God bless all the brave souls who put it all — everything — on the line just to show those black-hearted tyrants what Khamenei is made to mouth in the video: Their time is coming to an end."