Word
momentous
Phoneticsmo·men·tous, stress on the second syllable
US/moʊˈmɛntəs/
UK/məʊmˈɛntəs/
Definition
adj. very important because it will have a big effect on the future. You use this to describe a major event or decision.
adj. of great importance or significance, especially in its bearing on future events. Often used to describe historical turning points or life-changing decisions.
Examples
“The two countries signed a momentous peace treaty today.”
“Graduating from university is a momentous occasion that marks the start of a new chapter in life.”
“The discovery of the new vaccine was a momentous achievement that promised to alter the course of global public health for generations to come.”
Examples
simple
“The two countries signed a momentous peace treaty today.”
contextual
“Graduating from university is a momentous occasion that marks the start of a new chapter in life.”
complex
“The discovery of the new vaccine was a momentous achievement that promised to alter the course of global public health for generations to come.”
Usage
Typically used as an attributive adjective before a noun like 'decision', 'occasion', or 'event'.
Pitfall
a momentary decision
a momentous decision
Learners confuse 'momentous' (important) with 'momentary' (lasting only a short time).
Real-World Examples
“Has it happened before that such a momentous case with potential ramifications for voting has come to the Supreme Court this close to an election?” “As for Trent, our plucky project manager, the launch marks the end of a momentous 12 months.” Etymology
From moment (“weight, importance”) + -ous.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.
Word family
NOUN
ADJECTIVE
- 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.C1 AdvancedIELTSIELTSInternational English Language Testing SystemThe 0–9 band test co-owned by the British Council, IDP, and Cambridge. Used for university entry, work, and migration.7.0–8.0TOEFL 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: 5.0–5.595–113TOEICTOEICTest of English for International CommunicationETS's workplace English test, big in Japan and Korea. Listening & Reading scores 10–990 and tops out at C1.945–990
- Frequency
- Occasional
- Level
- C1 · Advanced
- Updated
- アルファベット
- 読み方の一覧 →
QR code
englishreference.com/q/momentous