Meaning of UNDERLAY in English

UNDERLAY

[un.der.lay] vt -laid ; -lay.ing (bef. 12c) 1: to cover, line, or traverse the bottom of: give support to on the underside or below

2: to raise or support by something laid under

[2]un.der.lay n (1612): something that is or is designed to be laid under

Merriam-Webster English vocab.      Английский словарь Merriam Webster.