The Collaborative International Dictionary
Onerous cause
Onerous \On"er*ous\, a. [L. onerosus, fr. onus, oneris, a load,
burden: cf. F. on['e]reux.]
Burdensome; oppressive. ``Too onerous a solicitude.''
--I.
Taylor.
Onerous cause (Scots Law), a good and legal consideration; -- opposed to gratuitous.