undersurface

[ uhn-der-sur-fis ]
/ ˈʌn dərˌsɜr fɪs /

noun

underside; bottom surface.

adjective

submerged; under the surface, as of water, earth, etc.: the undersurface speed of a submarine.

Origin of undersurface

First recorded in 1725–35; under- + surface
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

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