Underneath is defined as below or on a lower level.
(adverb)An example of underneath used as an adverb is in the sentence, "The plate is underneath the bowl," which means that the bowl sits on top of the plate.
See underneath in Webster's New World College Dictionary
adverb
Origin: ME undernethe < OE underneothan < under, under + neothan, below; akin to neothera, nether
adjective
noun
See underneath in American Heritage Dictionary 4
adverb
Origin:
Origin: Middle English undernethe
Origin: , from Old English underneothan
Origin: : under, under; see under
Origin: + neothan, below; see beneath
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