noun / verb

underlay

un-der-LAY/ˌʌndərˈleɪ/

Support provided by material placed beneath a surface.

The worker places soft underlay beneath the rug.

A worker slides cushioning felt beneath a rug, clear under-layer providing support.

Etymology

Under supplies the position, while lay means to cause something to lie or rest. Together they describe supporting something by placing another thing beneath it—the same practical relationship expressed by a supporting layer or lining.

More examples

She underlaid the carpet with felt.
They are underlaying the floor covering.
Several underlays were compared.

Forms

underlay · underlays · underlaid · underlaying

Similar words

padding: Cushioning that can be placed anywhere.
lining: An inner covering, not necessarily beneath a floor surface.