折おりたたみナイフ

お

り

た

み

ナ

イ

フ

Meanings

1

folding knife; pocket knife

A knife with a blade that folds into the handle. Common types include penknives and clasp-knives.

I take a folding knife when I go camping.

彼かれはポケットから折おりたたみナイフを取とり出だした。

He took a folding knife out of his pocket.

ポケットナイフ
ポケットナイフ is a more general term for any small knife carried in a pocket, while 折りたたみナイフ specifically emphasizes the folding mechanism.
肥後守ひごのかみ
肥後守 is a traditional Japanese folding knife without a locking mechanism, often associated with schoolchildren in the past. 折りたたみナイフ is a broader, modern term.

折おりたたみナイフ
Standard spelling using 折りたたみ (folding) and ナイフ (knife).
折おり畳たたみナイフ
Alternate spelling with the kanji 畳 for たたみ; less common but still seen.

Compound of 折りたたみ (folding) + ナイフ (knife). The word is a straightforward modern formation.