massless

[ mas-lis ]
/ ˈmæs lɪs /

adjective Physics.

pertaining to an elementary particle having zero rest mass, as a photon.

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seclusion

Origin of massless

First recorded in 1875–80; mass + -less

OTHER WORDS FROM massless

mass·less·ness, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

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