ˈōnəs noun
( -es )
Etymology: Latin — more at onerous
1.
a. : something (as a task, duty, responsibility) that involves considerable difficulty or annoyance or necessitates rather strenuous effort or results in notable strain or fatigue : burden
the job of caring for his dependents was a real onus
believe it to be the onus on every man to add … to the sum total of human knowledge — Douglas Carruthers
b. : something distasteful or objectionable and difficult to bear: as
(1) : a disagreeable necessity of doing something
free of all onus of retort or comment — Richard Blaker
(2) : blame
tried to shift the onus for causing the war onto the other country
adroitly transfer the onus from the accused to the accusers — Eugene Lyons
(3) : stigma
excusing himself ahead of time so that the onus would be less if his failure was realized — Norman Mailer
2. or onus pro·ban·di -prōˈbanˌdī, -ndē : burden of proof
put forth a theory that left the onus squarely on him