If you refer to a decision, event, or change as momentous, you mean that it is very important, often because of the effects that it will have in the future.
...the momentous decision to send in the troops.
Synonyms: significant, important, serious, vital More Synonyms of momentous
momentous in British English
(məʊˈmɛntəs)
adjective
of great significance
Derived forms
momentously (moˈmentously)
adverb
momentousness (moˈmentousness)
noun
momentous in American English
(moʊˈmɛntəs; məˈmɛntəs)
adjective
of great moment; very important
a momentous decision
Derived forms
momentously (moˈmentously)
adverb
momentousness (moˈmentousness)
noun
Examples of 'momentous' in a sentence
momentous
We have had momentous days before and survived them all.
Times, Sunday Times (2016)
The book goes into little detail on what seems quite a momentous change.
Times, Sunday Times (2014)
The sense that you are a part of an unparalleled history can play momentous tricks.
Times, Sunday Times (2014)
This day will be momentous in the history of all time.
Times, Sunday Times (2014)
Many other people must adjust to these momentous changes.
Harris, Marvin Cultural Anthropology (1995)
One of the reasons his career feels so weighty is because of the momentous history it spans.
Times, Sunday Times (2011)
It was designed as a golden souvenir of a momentous day.
Times, Sunday Times (2012)
But there was a momentous change of attitude in that sentence.
Times, Sunday Times (2010)
It was a momentous day for me.
The Sun (2010)
Americans sense their nation is on the threshold of momentous change.
The Sun (2008)
This has been a momentous day.
Times, Sunday Times (2014)
None of these changes was momentous.
Philip Marsden The Barefoot Emperor: An Ethiopian Tragedy (2007)
The unbroken bottle was the first hitch in what had been a momentous day for the Duchess.
Times, Sunday Times (2007)
It's one of those momentous days alongside changing the offside law.
The Sun (2013)
To explore the history of our streets is to chart momentous social change and the ebb and flow between enormous wealth and terrible poverty.
Times, Sunday Times (2014)
The relationship of his art to his country's dark and momentous history is perhaps the most powerful force that shapes this retrospective.
Times, Sunday Times (2011)
We should not forget the momentous changes occurring in Tunisia and Egypt.
Times, Sunday Times (2011)
The deciding shootout leg was summed up in commentary at the time as the'most momentous in darts history '.
The Sun (2015)
In other languages
momentous
British English: momentous /məʊˈmɛntəs/ ADJECTIVE
A momentous event is very important.
...the momentous decision to get married.
American English: momentous
Arabic: هَامٌ جِداً
Brazilian Portuguese: importantíssimo
Chinese: 重大的
Croatian: značajan
Czech: důležitý
Danish: afgørende
Dutch: gewichtig
European Spanish: trascendental
Finnish: merkittävä
French: capital
German: bedeutsam
Greek: βαρυσήμαντος
Italian: molto importante
Japanese: きわめて重大な
Korean: 중대한
Norwegian: av stor betydning
Polish: doniosły
European Portuguese: importantíssimo
Romanian: de seamă
Russian: значительный
Latin American Spanish: trascendental
Swedish: mycket viktig
Thai: ซึ่งมีความสำคัญมาก
Turkish: çok önemli
Ukrainian: пам'ятний
Vietnamese: quan trọng
Chinese translation of 'momentous'
momentous
(məuˈmɛntəs)
adj
重大的 (zhòngdà de)
(adjective)
Definition
of great significance
the momentous decision to send in the troops
Synonyms
significant
It is the first drug that seems to have a significant effect on this disease.
important
an important economic challenge to the government
serious
I regard this as a serious matter.
vital
a blockade which could cut off vital oil and gas supplies
critical
The incident happened at a critical point in the campaign.
crucial (informal)
the most crucial election campaign in years
grave
He says the situation in his country is very grave.
historic
the historic changes in Eastern Europe
decisive
a decisive victory in the elections
pivotal
The Court of Appeal has a pivotal role in the English legal system.
fateful
What changed for him in that fateful year?
weighty
Surely such weighty matters merit a higher level of debate?
consequential
From a medical standpoint, a week is usually not a consequential delay.
of moment
earth-shaking (informal)
Opposites
trivial
,
trifling
,
insignificant
,
unimportant
,
inconsequential
Additional synonyms
in the sense of consequential
Definition
important or significant
From a medical standpoint, a week is usually not a consequential delay.
Synonyms
important,
serious,
significant,
grave,
far-reaching,
momentous,
weighty,
eventful
in the sense of critical
Definition
very important or dangerous
The incident happened at a critical point in the campaign.
Synonyms
crucial,
decisive,
momentous,
deciding,
pressing,
serious,
vital,
psychological,
urgent,
all-important,
pivotal,
high-priority,
now or never
in the sense of crucial
Definition
of exceptional importance
the most crucial election campaign in years
Synonyms
vital,
important,
pressing,
essential,
urgent,
momentous,
high-priority
Synonyms of 'momentous'
momentous
Explore 'momentous' in the dictionary
Additional synonyms
in the sense of decisive
Definition
having great influence on the result of something
a decisive victory in the elections
Synonyms
crucial,
significant,
critical,
final,
positive,
absolute,
influential,
definite,
definitive,
momentous,
conclusive,
fateful
in the sense of fateful
Definition
having important, and usually disastrous, consequences
What changed for him in that fateful year?
Synonyms
crucial (informal),
important,
significant,
critical,
decisive,
momentous,
portentous
in the sense of grave
Definition
serious and solemn in appearance or behaviour
He says the situation in his country is very grave.
Synonyms
serious,
important,
significant,
critical,
pressing,
threatening,
dangerous,
vital,
crucial (informal),
acute,
severe,
urgent,
hazardous,
life-and-death,
momentous,
perilous,
weighty,
leaden,
of great consequence
in the sense of historic
Definition
important in history, or likely to be seen as important in the future
the historic changes in Eastern Europe
Synonyms
significant,
notable,
momentous,
famous,
celebrated,
extraordinary,
outstanding,
remarkable,
ground-breaking,
consequential,
red-letter,
epoch-making
in the sense of important
Definition
of great significance, value, or consequence
an important economic challenge to the government
Synonyms
significant,
critical,
substantial,
grave,
urgent,
serious,
material,
signal,
primary,
meaningful,
far-reaching,
momentous,
seminal,
weighty,
of substance,
salient,
noteworthy
in the sense of pivotal
Definition
of crucial importance
The Court of Appeal has a pivotal role in the English legal system.
Synonyms
crucial,
central,
determining,
vital,
critical,
decisive,
focal,
climactic
in the sense of serious
Definition
concerned with important matters
I regard this as a serious matter.
Synonyms
important,
crucial (informal),
urgent,
pressing,
difficult,
worrying,
deep,
significant,
grim,
far-reaching,
momentous,
fateful,
weighty,
no laughing matter,
of moment or consequence
in the sense of vital
Definition
essential or highly important
a blockade which could cut off vital oil and gas supplies
Synonyms
essential,
important,
necessary,
key,
basic,
significant,
critical,
radical,
crucial (informal),
fundamental,
urgent,
decisive,
cardinal,
imperative,
indispensable,
requisite,
life-or-death,
must-have
in the sense of weighty
Definition
important or serious
Surely such weighty matters merit a higher level of debate?