certainly
29 synonyms and 7 antonyms for certainly, grouped by meaning and by how common each one is.
Adv — Without any doubt; definitely.
Synonyms
Everyday swaps
Common words most readers know — safe in any writing.
Less common
Still standard English, but they carry more weight.
Rare, literary or technical
Precise, but they will stand out — check the sense before using one.
Antonyms
How to use certainly
The word patterns that sound natural to a native speaker.
Etymology
From Middle English certeynly; equivalent to certain + -ly.
Full origin of certainly →Frequently asked questions
What does “certainly” mean?
The word “certainly” means without any doubt; definitely. In plain terms, without doubt, or as an emphatic "yes".
How do you pronounce “certainly”?
“Certainly” is pronounced SUR-tn-lee (/ˈsɝ.tn̩.li/ in IPA).
How do you use “certainly” in a sentence?
Here is “certainly” used in a sentence: “This is certainly the best coffee in town.”
What is another word for “certainly”?
Words with a similar meaning to “certainly” include damn right, damn straight, fo shizzle, for sure, oh yeah and wye aye.
What is the opposite of “certainly”?
The opposite of “certainly” — its antonyms — are arguably, conditionally, debatably, deniably and doubtfully.
What part of speech is “certainly”?
“Certainly” is an adverb.
Is “certainly” a common word?
“Certainly” is a very common word in modern English, usually learned at around the A2 level.
How many meanings does “certainly” have?
“Certainly” has 2 distinct senses listed in this dictionary. The most common is: without any doubt; definitely.
What is the difference between certainly and surely?
Certainly expresses firm confidence that something is true or will happen — 'she will certainly win.' Surely often expresses hope or seeks agreement, with a slight hint of doubt — 'surely you agree?' Certainly sounds more definite, while surely can sound as though the speaker is checking or persuading.
What does certainly mean as a reply?
As a one-word answer, 'Certainly' is a polite, emphatic way of saying yes or 'of course.' It signals willing, confident agreement to a request — for example, 'Could you help me?' 'Certainly.' It sounds a little more formal and courteous than a simple 'sure' or 'yeah.'
Is certainly formal or informal?
Certainly is fairly neutral but leans slightly formal and polite, and it's common in professional or courteous speech. In casual conversation, people often reach for 'definitely,' 'for sure,' or 'of course' instead — though certainly fits comfortably in both formal and everyday settings.
What is an example of certainly in a sentence?
'The results are certainly impressive.' 'I will certainly be there by six.' 'It's certainly cold today.' In each sentence, certainly stresses that the speaker has no doubt at all about what they are saying, adding confidence and emphasis to the statement.