onus vs encumbrance

onus and encumbrance both are nouns.

Word	Noun	Adjective	Verb	Adverb
onus	Yes	No	No	No
encumbrance	Yes	No	No	No

As nouns, onus and encumbrance are synonyms defined as:

Other synonyms of onus include burden, incumbrance, load.

onus (noun)	encumbrance (noun)
an onerous or difficult concern	any obstruction that impedes or is burdensome
	an onerous or difficult concern
	a charge against property (as a lien or mortgage)