Related Clues:

• Place for hot air to escape
• Put nitrogen in to check gas exhaust
• Express train finally entering test
• Air conduit
• Go on a tweetstorm, say
• Hole allowing gas or air to escape
• Give free expression to — opening
• Opening race perhaps fails to start
• Clothes dryer attachment
• Part of a volcano
• Volcano's outlet
• Opening oven, tray's grabbed
• Let out at last
• Release; opening
• Express strong emotions