thud vs thump

thud and thump both are nouns.

Word	Noun	Adjective	Verb	Adverb
thud	Yes	No	Yes	No
thump	Yes	No	Yes	No

As nouns, thud and thump are synonyms defined as:

Other synonyms of thud include clump, clunk, thumping.

As verbs, thud and thump are synonyms defined as:

thud (noun)	thump (noun)
a heavy dull sound (as made by impact of heavy objects)	a heavy blow with the hand
	a heavy dull sound (as made by impact of heavy objects)

thud (verb)	thump (verb)
strike with a dull sound	hit hard with the hand, fist, or some heavy instrument
make a dull sound	move rhythmically
make a noise typical of an engine lacking lubricants	make a dull sound