noun
Refers to a short-bladed weapon, often a double-edged dagger. The reading あいくち is standard; ひしゅ is a rare alternative reading.
See also: 合い口 (あいくち)
彼は護身用に匕首を携帯していた。
He carried a dagger for self-defense.
時代劇では、匕首を使った暗殺シーンがよく出てくる。
In period dramas, assassination scenes using a dagger often appear.
Kana spelling is common in everyday writing, especially when the kanji is obscure.
短刀 is a general term for a short sword or dagger, while 匕首 specifically refers to a type of dagger, often with a double-edged blade and no guard.
合い口 can also mean 'dagger' in some contexts, but more commonly refers to the fit or compatibility between things. 匕首 is the specific term for the weapon.
The kanji 匕首 are ateji (characters used for their sounds) for the native Japanese word あいくち. The reading ひしゅ is a Sino-Japanese reading of the same characters, but it is rarely used.