— onerously , adv. — onerousness, onerosity /oh'neuh ros"i tee/ , n.
/on"euhr euhs, oh"neuhr-/ , adj.
1. burdensome, oppressive, or troublesome; causing hardship: onerous duties.
2. having or involving obligations or responsibilities, esp. legal ones, that outweigh the advantages: an onerous agreement.
[ 1350-1400; ME onerosus, equiv. to oner- (s. of onus ) burden + -osus -OUS ]
Syn. 1. heavy, crushing, grievous; irksome, galling.