The Meaning of Onus: What It Is and How To Use It

Do you know the definition of onus? This article will provide you with all of the information you need on the word onus, including its definition, etymology, usage, example sentences, and more!

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What does the word onus mean?

According to Collins English Dictionary and the American Heritage Unabridged Dictionary of the English Language,  the word onus is a noun that means a duty or responsibility. This is often used in the phrase “the onus is on” which means a responsibility is on a person or thing to do something. If the onus is on a landlord to get plumbing fixed, that means it is their responsibility, and not the tenant’s. The word onus is two syllabus – o-nus, and the pronunciation of onus is ˈəʊnəs. The plural of onus is onuses.

There are many different languages that also use words that mean onus. You may notice that many of these words look similar to one another. This is likely because they have a common origin. Often, languages that have a common language of origin, like Latin or Greek, will contain many cognates, which are words that look, sound, and mean similar things. This list of translations of onus is provided by Word Sense

  •  French: obligation‎ (fem.)
  •  Hungarian: kötelezettség‎
  •  Ukrainian: зобов’язання‎
  •  Georgian: ვალდებულება‎
  •  Danish: pligt‎ (common)
  •  Spanish: comprometerse‎
  •  Finnish: sitoutuminen‎
  •  Arabic: وَاجِب‎ (masc.)
  •  Czech: závazek‎ (masc.)
  •  Mandarin: 義務‎, 义务‎ (yìwù), 責任‎, 责任‎ (zérèn)
  •  Romanian: obligare‎ (fem.), obligație‎
  •  Russian: обяза́тельство‎ (neut.), долг‎ (masc.)
  •  Portuguese: obrigação‎ (fem.)
  •  Greek: υποχρέωση‎ (fem.)
  •  Belarusian: абавяза́цельства‎ (neut.), абавя́зак‎ (masc.)
  •  Swedish: skyldighet‎ (common)
  •  Vietnamese: nghĩa vụ‎ (義務‎)
  •  Japanese: 義務‎ (ぎむ, gimu), 責任‎ (せきにん, sekinin)
  •  Irish: oibleagáid‎ (fem.)
  •  German: Verpflichtung‎ (fem.), Pflicht‎ (fem.)
  •  Korean: 의무‎ (義務‎)
  •  Scottish Gaelic: comain‎ (fem.), còir‎ (fem.)
  •  Tagalog: harapin‎

What is the origin of the word onus?

According to Etymonline, the word onus comes from the Latin onus which is a word that means load or burden Figuratively, this was used to mean a tax, expense, trouble or difficulty. This comes from the PIE root en-es, which is also the source of Sanskrit anah meaning cart or wagon. This then spurred the Legal Latin onus probandi meaning burden of proof or the task of proving what has been alleged. The word onus has been used in the English language since the 1640s in the 17th century.

What are synonyms and antonyms of onus?

There are many different words that one can use in place of the word onus. These are called synonyms, which are words and phrases that have the same meaning as another word or phrase. Synonyms are very useful English grammatical devices to know because they can help you to avoid repeating yourself as well as to expand your vocabulary. This list of synonyms for the word onus is provided by Power Thesaurus

  •   devoir
  •   accountableness
  •   loads
  •   role
  •   weight
  •   commitment
  •   burdened
  •   answerability
  •   baton
  •   hardship
  •   debt
  •   task
  •   strain
  •   obligations
  •   smear
  •   black mark
  •   drag
  •   blameworthiness
  •   trial
  •   impediment
  •   blemish
  •   charge
  •   cumbrance
  •   burden of proof
  •   difficulty
  •   stain
  •   cross
  •   encumbrance
  •   tax
  •   culpability
  •   boundness
  •   liability
  •   workflow
  •   concern
  •   trouble
  •   reproach
  •   albatross
  •   dead weight
  •   mantle
  •   amenability
  •   burdens
  •   accusation
  •   smirch
  •   burden
  •   impedimenta
  •   duty
  •   payload
  •   loaded
  •   blame
  •   guiltiness
  •   loading
  •   load
  •   burthen
  •   disadvantage
  •   blot
  •   shipment
  •   responsibility
  •   taint
  •   slur
  •   assignment
  •   mantles
  •   affliction
  •   bar sinister
  •   accountability
  •   attaint
  •   deadweight
  •   commission
  •   spot
  •   call
  •   hindrance
  •   imposition
  •   mark of cain
  •   black eye
  •   requirement
  •   incubus
  •   odium
  •   cargo
  •   consignment
  •   freight
  •   stigma
  •   obligation
  •   pressure
  •   brand
  •   millstone
  •   function
  •   fault
  •   worry
  •   guilt
  •   indebtedness
  •   tarnish
  •   care
  •   white elephant
  •   call of duty
  •   aspersion
  •   ought
  •   blur
  •   incumbrance
  •   reflection
  •   brunt
  •   ordeal

There are also many different words that mean the opposite of the word onus. These opposite words are called antonyms. Antonyms are also useful to know if you are trying to expand your English language vocabulary. This list of antonyms is also provided by Power Thesaurus

  •  help
  •  beer and skittles
  •  forfeit
  •  irresponsibility
  •  lack of commitment
  •  freedom
  •  impassiveness
  •  earnings
  •  unburden
  •  disorientation
  •  exoneration
  •  ready money
  •  consider
  •  blank
  •  advantage
  •  praise
  •  aid
  •  irresponsibleness
  •  exculpation
  •  blanket of indifference

How can the word onus be used in a sentence?

The word onus can be used in many different ways in the English language. Using words in a sentence is a great way to learn their definitions. You can also try making flashcards or quizzes to test your knowledge of the definitions of different English language words. Try using this word in a sentence today! Several examples of onus are below to help get you started.

The onus was on the person who caused the offense to apologize and make it right. They are the owner of the responsibility for their own behavior and must make the whole thing right. 

The team members had a legal obligation to complete workplace safety training, and the onus of proof lies on their ability to complete the safety tasks.

The prosecution put the onus of the disagreement on the parties themselves. The civil case did not need to be elevated to the court level. The judge was frustrated at the waste of time.

The onus was on the student to reveal to his teacher that he had cheated. No one else knew, but the guilt was eating away at him and he knew he had to tell the truth. When he told her, she was very disappointed but allowed him to retake the test on his own because he fessed up. 

The lower-income Americans bore the majority of the onus for the economic downturn, though they were unable to do anything to stop it. They found a real challenge when they received hardly any tax refund and the burden of responsibility was left on them, not the businesses.

Overall, the word onus means an obligation, duty or responsibility. This word is of Legal Latin origins. 


  1. onus: meaning, origin, translation | Word Sense 
  2. Onus synonyms – 614 Words and Phrases for Onus – Page 2 | Power Thesaurus 
  3. Onus antonyms – 20 Opposites of Onus | Power Thesaurus 
  4. Onus definition and meaning | Collins English Dictionary 
  5. onus | Origin and meaning of onus | Online Etymology Dictionary