doodlebug vs robot bomb

doodlebug and robot bomb both are nouns.

Word	Noun	Adjective	Verb	Adverb
doodlebug	Yes	No	No	No
robot bomb	Yes	No	No	No

As nouns, doodlebug and robot bomb are synonyms defined as:

doodlebug and robot bomb: a small jet-propelled winged missile that carries a bomb

Other synonyms of doodlebug include buzz bomb, flying bomb, V-1.

doodlebug (noun)	robot bomb (noun)
the larva of any of several insects	a small jet-propelled winged missile that carries a bomb
a small jet-propelled winged missile that carries a bomb
a small motor vehicle