鈍い

• Reading: にぶい
• Romaji: nibui
• Kanji breakdown: 鈍 (nibu/don) — dull, blunt, slow
• Pronunciation: /ni.bɯ.i/

Meaning

Dull; blunt; slow; obtuse. Describes a blade that is not sharp, a person who is slow to understand, senses that are weak, or movements that are sluggish.

An i-adjective with multiple applications: (1) a physical blade that is not sharp (鈍い刃, blunt edge), (2) slow mental processing (頭が鈍い, slow-witted), (3) dull or weak sensory perception (感覚が鈍い, diminished senses), and (4) sluggish physical reaction (動きが鈍い, slow movements). The common thread is a lack of sharpness or acuity. Contrast with 鋭い (surudoi, sharp/keen).

Examples

1. このナイフは刃が鈍くて、パンを切るのに苦労した。 This knife has such a dull blade that I struggled just to cut bread.
2. 痛みの感覚が鈍い人は、怪我に気づかないことがある。 People with a dull sense of pain may not notice when they're injured.
3. 彼は反応が鈍いが、一度理解すれば誰よりも深く考える。 He's slow to react, but once he understands something, he thinks more deeply about it than anyone.

Usage Guide

Context: everyday speech, physical descriptions, personality commentary

Tone: neutral

Origin & History

From Old Japanese 鈍 (nibu), meaning dull or blunt. The kanji 鈍 combines 金 (metal) with a component suggesting roundness or obtuseness — a blade without a fine edge.

Cultural Context

Era: Ancient–Modern

Generation: All ages

Social background: Universal