expression, noun-modifying (irregular)
quite unlike; bearing no resemblance
Fixed expression used prenominally to emphasize a complete lack of resemblance. Often used in the pattern 〜に似ても似つかぬ to mean 'completely unlike ~'. The form 似ても似つかない is a more common modern variant.
See also: 似ても似つかない
彼は父親に似ても似つかぬ顔立ちだ。
He has features that are quite unlike his father's.
その絵は本物に似ても似つかぬ出来だった。
The painting was a result that bore no resemblance to the real thing.