Consisting of a peculiar form of words.(adjective)
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Use "phraseological" in a sentence
"Longer idioms, like to be caught between the devil and the deep blue sea, "do not readily correlate with a given grammatical part of speech"; these he terms phraseological idioms."
"Why does this writer insist on a phraseological style that suggests the eurosceptics are a small minority?"
"It has verbal and phraseological peculiarities of its own."