blow off

verb

• To pass gas; to break wind, to fart.
• To vent, usually, to reduce pressure in a container.

  "The radioactivity was released when they blew off steam from the containment vessel."

• To let steam escape through a passage provided for the purpose.

  "The engine or steamer is blowing off."

• To shirk or disregard (a duty or person).

  "I decided to blow off the meeting and leave early."

• To forcibly disconnect something by use of a firearm or explosive device.

  "Her leg was blown off by a landmine."