onerousness

Onerousness refers to the state or quality of being onerous—that is, burdensome, troublesome, or oppressive. It characterizes obligations, duties, or costs that impose substantial difficulty, effort, risk, or expense on those who bear them.

Etymology derives from the Latin onerosus, meaning burdensome, connected to onus, burden. Through Old French and Middle English, the term evolved into its current use in law, economics, and everyday language to describe demands that are hard to bear.

In law, onerousness describes terms or obligations that are particularly burdensome. An onerous clause in a contract imposes significant duties, risks, or costs on one party, while an onerous contract is one whose obligations are disproportionately burdensome relative to the consideration received. In civil law traditions, the concept can influence assessments of validity or enforceability, and some systems provide remedies or relief when contract terms are deemed grossly onerous.

Economically and regulatorily, onerousness is used to describe high costs of compliance, administrative burdens, or regulatory requirements that impose substantial effort or expense. The assessment is often relative to the parties involved; what is onerous for one entity may not be for another, depending on resources, risk tolerance, and context.

Examples include debt instruments with punitive terms, or regulatory regimes that require extensive reporting with severe penalties for minor infractions. See also burdensomeness, hardship, onerous contract, and burden of compliance.