
[Late Latin, from Greek, from antiphrazein, to express by the opposite : anti-, anti- + phrazein, to speak; see phrase.]
antiphrasis
Adjective: antiphrastic.
The ironic or humorous use of words in a sense not in accord with their literal meaning, as in "a giant of three feet four inches."

An antiphrasis (
/ænˈtɪfrəsɪs/; from the Greek: ἀντί, antí, "opposite" and φράσις, phrásis, "diction") is a figure of speech in which a word or phrase is used to mean the opposite of its usual sense, especially ironically.
Ptolemy IV of Egypt: "By some historians [ Ptolemy IV of Egypt] is said to have poisoned his father, whence he received the surname of Philopater, by antiphrasis." [1]
"It was a bold antiphrasis that gave such a vernal title [Greenland] to this birth-place of icebergs."[2]
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