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box; case; chest; package; pack; crate
car (of a train, etc.)
counter for boxes (or boxed objects)
shamisen case; shamisen
public building; community building
この函を開けてみてよ。
Try opening this box.
函の中に手紙が入っている。
There's a letter inside the box.
大きな函に荷物を全部詰めて送ることにした。
I decided to pack everything into a big box and ship it.