simple past tense of underlie

(transitive) To lay (something) underneath something else; to put under. / (transitive) To provide a support for something; to raise or support by something laid under.

A layer (of earth, etc.) that lies under another; substratum. / A soft floor covering that lies under a carpet. / Anything that is underlaid.

plural of underlay

present participle of underlay

Misspelling of underlaid.

plural of underlayer

A layer that is below another layer. / (mining) A perpendicular shaft sunk to cut the lode at any required depth. / One who underlays.

To form a layer beneath another

plural of underlayment