stone fly vs stonefly

stone fly and stonefly both are nouns.

Word	Noun	Adjective	Verb	Adverb
stone fly	Yes	No	No	No
stonefly	Yes	No	No	No

As nouns, stone fly and stonefly are synonyms defined as:

stone fly and stonefly: primitive winged insect with a flattened body; used as bait by fishermen; aquatic gilled larvae are carnivorous and live beneath stones

Other synonyms of stone fly include plecopteran.

stone fly (noun)	stonefly (noun)
primitive winged insect with a flattened body; used as bait by fishermen; aquatic gilled larvae are carnivorous and live beneath stones	primitive winged insect with a flattened body; used as bait by fishermen; aquatic gilled larvae are carnivorous and live beneath stones