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lumen

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Lumen

Main Entry:: lu·men
Pronunciation:: \ˈlü-mən\
Function:: noun
Inflected Form(s):: plural lumens also lu·mi·na \-mə-nə\
Etymology:: New Latin lumin-, lumen, from Latin, light, air shaft, opening
Date:: 1873

1 : the cavity of a tubular organ or part <the lumen of a blood vessel> 2 : the bore of a tube (as of a hollow needle or catheter) 3 : a unit of luminous flux equal to the light emitted in a unit solid angle by a uniform point source of one candle intensity

— lu·mi·nal also lu·men·al

Listen to the pronunciation of lumenal

\-mə-n^əl\ adjective

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