mayfly vs dayfly

mayfly and dayfly both are nouns.

Word	Noun	Adjective	Verb	Adverb
mayfly	Yes	No	No	No
dayfly	Yes	No	No	No

As nouns, mayfly and dayfly are synonyms defined as:

mayfly and dayfly: slender insect with delicate membranous wings having an aquatic larval stage and terrestrial adult stage usually lasting less than two days

Other synonyms of mayfly include shadfly.

mayfly (noun)	dayfly (noun)
slender insect with delicate membranous wings having an aquatic larval stage and terrestrial adult stage usually lasting less than two days	slender insect with delicate membranous wings having an aquatic larval stage and terrestrial adult stage usually lasting less than two days