Definition of penny-in-the-slot in English:

penny-in-the-slot

adjective

British
  • Designating or relating to a machine or mechanical device (as a weighing machine, dispensing machine, etc.) actuated by the fall of a penny inserted through a slot or narrow opening.

noun

British
  • A penny-in-the-slot machine. rare.

Origin

Late 19th century; earliest use found in The Boston Globe. From penny + in + the + slot.

Pronunciation

penny-in-the-slot

/ˌpɛni ɪn ðə ˈslɒt/