訓 にぶ(い),にぶ(る),にぶ-,なま(る),なまく(ら) ・ 音 ドン
Sino-Vietnamese: độn
The metal radical 金 gives the meaning and 屯 the sound: a blunt metal blade. Sino-Vietnamese độn, as in ngu độn (dull-witted).
Stroke data: KanjiVG (CC BY-SA 3.0) — kanjivg.tagaini.net
このナイフは切れ味が鈍い。 (このないふはきれあじがにぶい)
This knife is dull.