file 13

US dated slang uncountable

(US, military slang, dated) A trash can, wastepaper basket.

Japanese Meaning

ごみ箱（ゴミを捨てるための容器。米軍の時代遅れのスラング表現として使われる）

After the briefing, he shoved the confidential memo into the file 13 without a second thought.

ブリーフィングの後、彼は機密メモを何の躊躇もなくゴミ箱に放り込んだ。

Sense（1）

(US, military slang, dated) A trash can, wastepaper basket.

Just put it in file 13. It doesn't warrant a response.