D defs.my
Entry 1 sense Webster, 1913

Undercroft

· Un·der·croft · IPA
01 n. A subterranean room of any kind; esp., one under a church (see Crypt), or one used as a chapel or for any sacred purpose.
  1. 1.
    A subterranean room of any kind; esp., one under a church (see Crypt), or one used as a chapel or for any sacred purpose.(Arch.) See: Crypt