perplex vs gravel

perplex is not a noun while gravel is a noun.

Word	Noun	Adjective	Verb	Adverb
perplex	No	No	Yes	No
gravel	Yes	No	Yes	No

As verbs, perplex and gravel are synonyms defined as:

Other synonyms of perplex include amaze, baffle, beat, bewilder, dumbfound, flummox, get, mystify, nonplus, pose, puzzle, stick, stupefy, vex.

perplex (noun)	gravel (noun)
	rock fragments and pebbles

perplex (verb)	gravel (verb)
make more complicated	be a mystery or bewildering to
be a mystery or bewildering to	cover with gravel
	cause annoyance in; disturb, especially by minor irritations