underlayer
nounUK /ˈʌndəˌleɪə/
US /ˈʌndərˌleɪər/
An underlayer is a layer that sits underneath another layer.
The painter applied an underlayer of white paint before the bright blue.
RELATED WORDS
OTHER MEANINGS
2. A hidden or less obvious part of something that supports what is seen.
Beneath the cheerful story lies an underlayer of sadness.
3. A layer of material placed under another for support or protection.
The carpet has a soft underlayer to make it feel thicker.
4. In geology, a rock layer lying beneath another layer.
The miners dug through the topsoil to reach the underlayer of clay.