Definition from Wiktionary, the free dictionary
- (colloquial) Excited or agitated; heated up.
He was het up about his chest pains.
1914, Edgar Rice Burroughs, The Mucker, HTML edition, The Gutenberg Project, published 2009:
- "I reckon," he said, directing his remarks toward no one in particular, "that we've all been rather hasty in this matter, being het up as we were with the strain of what we been through an' so it seems to me, …