sleeper

/ˈslipər/
noun
  1. A person who is sleeping or who sleeps in a particular way.
    • The hotel has special rooms for light sleepers.
    • My brother is a heavy sleeper who never hears his alarm.
    • The baby is a light sleeper and wakes up at any noise.
  2. A train car with beds for passengers to sleep in overnight.
    • We took a sleeper from Chicago to Los Angeles.
    • The sleeper car had comfortable bunks and clean sheets.
    • She booked a ticket on the overnight sleeper to save on a hotel.
  3. A movie, book, or product that becomes unexpectedly successful.
    • Investors are looking for the next sleeper stock in the tech industry.
    • The novel was a sleeper, selling millions after a slow start.
    • That low-budget film was a sleeper hit at the box office.
  4. A spy or agent who remains inactive for a long time before being activated.
    • The police arrested a sleeper agent who had been living quietly for years.
    • The novel's plot involves a sleeper cell in a small town.
    • Intelligence agencies worry about sleeper operatives in major cities.
  5. A heavy wooden or concrete beam used to support railroad tracks.
    • The train rattled over the steel rails bolted to the sleepers.
    • Workers replaced the old wooden sleepers with concrete ones.
    • A broken sleeper caused the track to shift slightly.
  6. A piece of clothing, especially a one-piece garment for a baby, worn for sleeping.
    • She bought a cute sleeper with little bears on it.
    • The sleeper has zippers for easy diaper changes.
    • The baby wore a warm fleece sleeper to bed.
What does "sleeper" mean? | whatsthatwordmean | whatsthatwordmean