drops a brick

Verb

drop a brick (third-person singular simple present drops a brick, present participle dropping a brick, simple past and past participle dropped a brick)

1. (UK, idiomatic) To commit a faux pas, especially in speech, such as by tactlessly speaking of a subject that should not be mentioned.
   • It was on one of those Tuesdays that I dropped a brick, the memory of which still haunts me after more than forty years. A very loquacious lady, whom I had never seen before, appeared to be talking through her nose. “Don't you think,” I said to one of my neighbours, by way of starting conversation...1978, Ambroise Vollard, translated by Violet M. MacDonald, Recollections of a Picture Dealer, Dover Publications, published 2003, page 28
2. Used other than figuratively or idiomatically: see drop, brick.
   • The clumsy builder dropped a brick on his toe.