also: くちのへらん
expression, noun-modifying (irregular)
always having a comeback; fast-talking; never at a loss for words
Describes someone who always has a quick, often sharp or argumentative reply; frequently used in a derogatory or critical way. The expression is a fixed prenominal phrase modifying a noun (e.g., 口の減らない人).
See also: 口が減らない
He's a man who always has a comeback; no matter what you say, he talks back.
口の減らないやつだな、少しは黙ったらどうだ。
What a fast-talking guy; why don't you shut up for a bit?
Standard kanji-kana spelling for this fixed expression.
Search-only colloquial contraction; 減らん is a dialectal or casual negative form.
Search-only kana spelling of the contracted form.
From 口 (mouth) + 減らない (negative of 減る, 'to decrease'), literally 'mouth that does not decrease', implying a never-ending flow of words. The exact origin is uncertain, but it is a common idiomatic expression.