Simple past tense and past participle of heighten.(verb)
Increased in intensity or concentration; elevated, stepped-up(adjective)
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Use "heightened" in a sentence
"COOPER: Thelma, if tens of thousands of people are going through, what exactly are customs agents doing during this -- what they call the heightened alert?"
"COOPER: Thelma, with tens of thousands of people going through, what exactly are customs agents doing during this, what they call the heightened alert?"
"The constant trouble into which the narrator gets himself seems contrived, which isn't helped by the fact that the setting, against which this action ought to be heightened, is depicted cursorily at best."