Phalangium opilio vs daddy longlegs

Phalangium opilio and daddy longlegs both are nouns.

Word	Noun	Adjective	Verb	Adverb
Phalangium opilio	Yes	No	No	No
daddy longlegs	Yes	No	No	No

As nouns, Phalangium opilio and daddy longlegs are synonyms defined as:

Phalangium opilio and daddy longlegs: spiderlike arachnid with a small rounded body and very long thin legs

Other synonyms of Phalangium opilio include harvestman.

Phalangium opilio (noun)	daddy longlegs (noun)
spiderlike arachnid with a small rounded body and very long thin legs	long-legged slender flies that resemble large mosquitoes but do not bite
	spiderlike arachnid with a small rounded body and very long thin legs