noun-modifying (irregular)
sternly handsome; ruggedly good-looking; manly
Describes a man's face or appearance that is attractively rugged, mature, or sharp-featured, often with a hint of severity. Used prenominally (e.g., 苦味走った顔).
彼は苦味走った顔立ちで、女性に人気がある。
He has a sternly handsome face and is popular with women.
苦味走った中年男性が渋い声で話し始めた。
A ruggedly handsome middle-aged man began speaking in a husky voice.
From 苦味 (にがみ, 'bitterness') + 走る (はしる, 'to run'), literally 'bitterness has run through'. The expression figuratively describes a face that has a sharp, mature, slightly severe quality, as if seasoned by life's hardships.