[1] : The Collaborative International Dictionary of English v.0.48

dayfly \day"fly`\ d=a"flimac`, n. zool.
   a neuropterous insect of the genus ephemera and related
   genera, of many species, and inhabiting fresh water in the
   larval state; the ephemeral fly; -- so called because it
   commonly lives but one day in the winged or adult state. see
   ephemeral fly, under ephemeral.
   1913 webster
see also:
ephemera ephemeral fly ephemeral 

[2] : WordNet (r) 2.0

dayfly
     n : slender insect with delicate membranous wings having an
         aquatic larval stage and terrestrial adult stage usually
         lasting less than two days syn: mayfly, shadfly
see also:
mayfly shadfly 

Dayfly >> D Words
Dayfly, definition of term: Dayfly
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