brain-teaser

noun

1. informal.
   a difficult problem

Example Sentences

Given that the controllers of the world’s two main nuclear arsenals both claim to be champions of the Christian cause, the question is topical, not just an academic brain-teaser.

From Economist

An arts-themed brain-teaser will be published on 28 December, with others on film and TV to be published on 29 and 30 December.

From BBC

This year’s winner is akin to the Blue Dress brain-teaser that divided your social media feeds into warring factions not so long ago.

From Salon

Bernice Gordon, 101, a prolific crossword constructor whose puzzles were published in major newspapers and brain-teaser books, died Thursday in Philadelphia.

From Seattle Times

An arts-themed brain-teaser will be published on 28 December, with others on TV and music to be published on 29 and 30 December.

From BBC

Related Words

• enigma
• mystery
• riddle