How to say "flies" in Japanese

• フライズ
  nounA less common term, covering only the theatrical sense: the area over the stage of a theater where scenery and equipment are hung. Stagehands use it when talking about scenery raised above the stage.
• 社会の窓しゃかいのまど
  expression, nounThe trouser sense: the fly or zipper on trousers. It is a jocular, humorous euphemism (literally "society's window"), typically used to tease someone whose flies are undone, not a neutral term.
  社会しゃかいの窓まど、開ひらいてますよ。↗

  Your fly's open.

Use 「フライズ」 only for the theatrical sense, the area above a theater stage; for the fly on trousers, 「社会の窓」 is a jocular, humorous euphemism rather than a neutral word, and both are less common.

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

• フライズflies (area over the stage of a theater)
• 社会の窓しゃかいのまどfly (on trousers)