開あけっ放ぱなす

godan verb (-su)

leave open; keep open

Used for doors, windows, or other openings that are left open, often carelessly or intentionally. The っ adds a colloquial, emphatic feel compared to 開け放す.

• 誰だれかがドアを開あけっ放ぱなしたまま出でかけた。

  Someone went out leaving the door open.

• 窓まどを開あけっ放ぱなして寝ねたら風邪かぜを引ひいた。

  I caught a cold because I slept with the window left open.