But not profanity!
A word we could use nearly everyday, really. We don’t think of it that way, but people often say “Promise me that…” I don’t know about threatening them with curses though.
adjure, v.
1. To put (one) to his oath; ‘to impose an oath upon another, prescribing the form in which he shall swear,’ J.; to bind under the penalty of a curse. Obs.
2. To charge or entreat (any one) solemnly or earnestly, as if under oath, or under the penalty of a curse. Const. inf. or subord. clause.