Word
ought
US/ˈɔt/
UK/ˈɔːt/
Definitions
01duty or obligation
B1 · Intermediate Formal
v. used to say that someone has a duty to do something because it is the right thing to do.
v. expresses moral or legal obligation or duty. It is followed by the 'to'-infinitive and does not change form for person or number.
“We ought to help our neighbours while they are away on holiday.”
“Citizens ought to consider the long-term environmental consequences of their daily consumption habits before dismissing new regulations.”
Usage
Always followed by 'to' plus the base form of the verb; in negatives, 'ought not to' is the standard formal construction.
Pitfall
You ought go to the doctor.
You ought to go to the doctor.
Unlike 'should' or 'must', 'ought' requires 'to' before the following verb.
02probability or expectation
B2 · Upper Intermediate Formal
v. used to say that you expect something to happen based on what you know.
v. indicates a strong logical probability or expectation that a particular state or event will occur.
“The bus ought to be here in five minutes if the traffic is light.”
“Given the current economic indicators, the central bank ought to announce a reduction in interest rates by the end of the quarter.”
Usage
Functions as a modal of deduction, similar to 'should' in its epistemic sense.
03what should be
C2 · Proficiency Countable noun Academic · Formal
n. an idea of what is right or how things should be, rather than how they actually are.
n. refers to an ideal state or a moral imperative, often contrasted with 'is' in philosophical contexts.
“There is often a big difference between the 'is' and the 'ought' in politics.”
“The philosopher spent his career exploring the gap between the 'is' of human nature and the moral 'ought' of ethical theory.”
Teaching tip
This noun use is rare outside of academic or philosophical discussions regarding ethics.
Antonyms
Collocations
Common phrases and expressions where native English speakers use the word “ought” in context.
Verb
01. ought to be
“The train ought to be here by now according to the schedule.”
verb + infinitive
02. ought to have done
“I really ought to have done my homework earlier this weekend.”
verb + infinitive
03. ought to help
“We ought to help our neighbors while they are away on vacation.”
verb + infinitive
04. ought to know
“You ought to know the rules before you start playing the game.”
verb + infinitive
05. ought to see a doctor
“You have a terrible cough and you really ought to see a doctor.”
verb + noun
06. ought to tell the truth
“He knew he ought to tell the truth even if it was difficult.”
verb + noun
Etymology
From Middle English oughte, aughte, aȝte, ahte, from Old English āhte, first and third person singular past tense of Old English āgan (“to own, possess”), equivalent to owe + -t. Cognate with Sanskrit ईश्वर (īśvará, “capable of, liable”).
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.
- Exam level
- CambridgeCambridgeCambridge English QualificationsThe exam suite from Cambridge University Press & Assessment, from A1 Movers up to C2 Proficiency. The benchmark names double as CEFR labels.B1 PreliminaryIELTSIELTSInternational English Language Testing SystemThe 0–9 band test co-owned by the British Council, IDP, and Cambridge. Used for university entry, work, and migration.4.0–5.0TOEFL iBTTOEFL iBTTest of English as a Foreign Language, Internet-Based TestETS's academic English test, the standard route for US university admissions. Scored 0–120, with a 1–6 scale since 2026.1–6 scale: 3.0–3.544–71TOEICTOEICTest of English for International CommunicationETS's workplace English test, big in Japan and Korea. Listening & Reading scores 10–990 and tops out at C1.550–784
- Frequency
- Common
- Level
- B1 · IntermediateOxford
- Updated
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