n. 词义反用法

[ noun ]
the use of a word in a sense opposite to its normal sense (especially in irony)
<noun.communication>

Antiphrasis \An*tiph"ra*sis\, n. [L., fr. Gr. ?, fr. ? to
express by antithesis or negation.] (Rhet.)
The use of words in a sense opposite to their proper meaning;
as when a court of justice is called a court of vengeance.