Medical Dictionary
diurnal
adj di·ur·nal \dī-ˈərn-əl\
Medical Definition of DIURNAL
1
: having a daily cycle <diurnal rhythms>
2
a : of, relating to, or occurring in the daytime <diurnal activity> b : chiefly active during the daytime <diurnal mosquitoes>
—di·ur·nal·ly \-əl-ē\ adverb
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