How to say "crack" in Japanese

Choosing the right word

亀裂きれつCommon
nounA crack or fissure, typically a long, visible split in hard surfaces such as rock, concrete, or dry ground. The word of choice for cracks in the earth or in buildings.
耐震性たいしんせいの悪わるい建物たてものに亀裂きれつが生しょうじることもある。↗
Also cracks may form in buildings that aren't Earthquake proof.
クラックCommon
nounThe loanword for a crack, especially in technical contexts such as cracks in materials or devices. Use it when the katakana term fits naturally, as in engineering or product descriptions.
割れ目われめCommon
nounA crack, split, or crevice where something has broken or split apart, emphasizing the split itself rather than a hairline flaw. Suited to cracks in porcelain, wood, or other broken objects.
彼かれは割れ目われめをパテでふさいだ。↗
He stopped up the crack with putty.
ひびCommon
nounA crack or fissure, usually written in kana alone; a general, everyday word for a crack running through a surface, such as a cracked cup, wall, or windshield.
その茶碗ちゃわんにはひびがある。↗
The cup has a crack.
快音かいおんCommon
nounNot a physical crack at all: it means a pleasant, sharp sound, as in the crack of a baseball bat or the pleasing roar of an engine. It is seldom the word you want for a break in a surface.

For physical cracks and fissures, choose among 亀裂, 「割れ目」, 「ひび」, or the loanword 「クラック」; 快音 is only for the sharp, pleasing crack of a bat or engine.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

Japanese equivalents

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