doodlebug vs larva

doodlebug and larva both are nouns.

Word	Noun	Adjective	Verb	Adverb
doodlebug	Yes	No	No	No
larva	Yes	No	No	No

As nouns, larva is a hypernym of doodlebug; that is, larva is a word with a broader meaning than doodlebug:

doodlebug: the larva of any of several insects
larva: the immature free-living form of most invertebrates and amphibians and fish which at hatching from the egg is fundamentally unlike its parent and must metamorphose

doodlebug (noun)	larva (noun)
the larva of any of several insects	the immature free-living form of most invertebrates and amphibians and fish which at hatching from the egg is fundamentally unlike its parent and must metamorphose
a small jet-propelled winged missile that carries a bomb
a small motor vehicle