alarm bell

alarm bell (plural alarm bells)

1. Used other than with a figurative or idiomatic meaning: see alarm,‎ bell.
   • 2000, James Hadley Chase, An Ear to the Ground

     He put his foot on a concealed button under his desk and rang an alarm bell. He always had two strongarm men lolling around in an office down the passage.

2. (figuratively, usually in the plural) A sudden awareness of danger.
   • 1998, Michele Gillespie, Catherine Clinton, Taking off the white gloves: Southern women and women historians

     The specter of women in factories, women in schoolrooms, and women attending — a lot less addressing — public meetings set off alarm bells in the South.

   • 2010, John M Findley, Just Lucky

     I only got a glimpse of him, but alarm bells went off. He wasn't rushing over to give me a pat on the back for stopping to help.

   • 2011 October 1, Tom Fordyce, “Rugby World Cup 2011: England 16-12 Scotland”, in BBC Sport‎:

     England were shipping penalties at an alarming rate - five in the first 15 minutes alone - and with Wilkinson missing three long-distance pots of his own in the first 20 minutes, the alarm bells began to ring for Martin Johnson's men.

• “alarm bell” (US) / “alarm bell” (UK) in Oxford Dictionaries, Oxford University Press.