onus
OH-nuhs
/ˈoʊnəs/
A relatively heavy or difficult responsibility, duty, or burden of proof.
Often used in legal or formal debates to specify who has the duty to prove a claim or take action.
The story behind the word. Directly borrowed from the Latin 'onus', meaning a physical load, burden, or cargo. In classical Latin, it was used both for the heavy packs carried by Roman soldiers and for the legal duties of citizenship.
Word relationships
- burden: Burden can be physical, emotional, or financial, whereas onus is almost always intellectual, legal, or duty-bound.
- encumbrance: An encumbrance is an obstacle or hindrance, while an onus is a necessary, though heavy, duty.
- exemption: Freedom from an obligation or duty.
- advantage: A condition or circumstance that puts one in a favorable position.
Commonly confused with
- bonus: Bonus is a reward or extra benefit (from Latin 'good'), while onus is a heavy burden (from Latin 'load'). They are etymological opposites in tone!
Word family
- onerous (adjective): Involving an amount of effort and difficulty that is oppressively burdensome.
Collocations
- onus of proof
- onus lies on
- place the onus
Example sentences
- "In a criminal trial, the onus of proof lies entirely on the prosecution to establish guilt." Legal Proceedings
- "The onus is on the department head to ensure that all safety protocols are followed." Management
Memory hook
The word sounds like 'on us'. If a heavy task is 'on us', we bear the 'onus' of getting it done. If the duty is ON US, we bear the ONUS.
When not to use
Do not use to describe a physical weight or a light, casual task.
Fun facts
- The legal phrase 'onus probandi' is the Latin term for 'burden of proof' and is still used in courts today.
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