To underlay a thing is to give it a foundation or support by putting something sturdy under it. Underlay also means to be underneath.

Something that underlays something else provides a base for that thing, whether it's the foundation of a building, the paper backing of a decal, or the fundamental ideas of a theory. As a noun, underlay refers to the padding that's laid out under carpet and other kinds of flooring.

Definitions of underlay
  1. verb
    put (something) under or beneath
    “They underlaid the shingles with roofing paper”
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    type of:
    lay, place, pose, position, put, set
    put into a certain place or abstract location
  2. verb
    provide with a base, support, lining, or backing
    underlay the boards with joists”
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    type of:
    cater, ply, provide, supply
    give what is desired or needed, especially support, food or sustenance
  3. verb
    raise or support (the level of printing) by inserting a piece of paper or cardboard under the type
    underlay the plate”
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    type of:
    bring up, elevate, get up, lift, raise
    raise from a lower to a higher position
  4. noun
    a pad placed under a carpet
    synonyms: carpet pad, rug pad, underlayment
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    a carpet pad of thick felt
    type of:
    a flat mass of soft material used for protection, stuffing, or comfort
Word Family

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