thud vs crackle

thud and crackle both are nouns.

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

As verbs, crackle is a hypernym of thud; that is, crackle is a word with a broader meaning than thud:

Other hypernyms of thud include crunch, scranch, scraunch.

thud (noun)	crackle (noun)
a heavy dull sound (as made by impact of heavy objects)	glazed china with a network of fine cracks on the surface
	the sharp sound of snapping noises

thud (adjective)	crackle (adjective)
	having the surface decorated with a network of fine cracks, as in crackleware

thud (verb)	crackle (verb)
strike with a dull sound	to become, or to cause to become, covered with a network of small cracks
make a dull sound	make a crushing noise
make a noise typical of an engine lacking lubricants	make a crackling sound