- (Usually pronounced [[t]ɪ̱r-[/t]] before an unstressed syllable, and [[t]ɪr-[/t]] before a stressed syllable.)Ir- is added to words that begin with the letter `r' to form words with the opposite meaning.
His behaviour was becoming increasingly irrational.
...its mixture of satirical wit, irreverence and spontaneity.
English dictionary. 2008.