antiphrasis
An`tiph´ra`sis
Noun 1. antiphrasis - the use of a word in a sense opposite to its normal sense (especially in irony)
rhetorical device - a use of language that creates a literary effect (but often without regard for literal significance)
irony - a trope that involves incongruity between what is expected and what occurs

"But Brutus is an honorable man....

Antiphrasis- the use of a word in a sense opposite to its normal sense.
Try thinking about antiphrasis in more of an ironic sense.
Consider this example: You'll be tried by an impartial jury of your peers in a court of vengeance.

Hi
Can I call you Wott for short? Welcome to the board Wott! I hope you wotted what you were doing when you entered the madhouse.
Zed

However did you discover one of Doctor Bill's old posts to which to respond?

Isn't "I could care less" a typical example

Or does the term apply only to a single word

Speaking of Bill, or rather having written of him, is he around these days?