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
Origin: ME undernethe < OE underneothan < under, under + neothan, below; akin to neothera, nether
See underneath in American Heritage Dictionary 4
Origin: Middle English undernethe
Origin: , from Old English underneothan
Origin: : under, under; see under
Origin: + neothan, below; see beneath.
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