joist

/dʒɔɪst/
noun
  1. A long, thick piece of wood, metal, or concrete used to support a floor or ceiling in a building.
    • The carpenter installed new wooden joists to strengthen the floor.
    • We could see the steel joists holding up the ceiling of the old warehouse.
    • The house's floor joists were damaged by termites and needed to be replaced.
Synonyms