Definition of brain trick in English:

brain trick

noun

  • 1A clever invention or stratagem (obsolete).

  • 2A delusion or illusion; a way in which the brain operates; a trick played by the brain.

  • 3An exercise for the brain; a puzzle.

Origin

Early 17th century; earliest use found in John Marston (bap. 1576, d. 1634), poet and playwright.