onerous
adj.adj. describing a task or duty that is very difficult, boring, or unpleasant to do.
adj. characterised by being burdensome, tedious, or difficult to perform. Often used to describe professional or legal obligations that are perceived as a heavy responsibility.
The new job has many onerous duties.
The legal team warned that the contract contained several onerous clauses that would be difficult to fulfill.
While the position offers a high salary, the onerous nature of the administrative tasks often leads to high staff turnover within the first year.
From Middle English onerous, from Middle French onereux, from Old French onereus, from Latin onerosus (“burdensome”), from onus (“load”). Compare exonerate.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.
Last updated May 19, 2026