undoubtedly
uhn-DOW-tihd-lee
Undoubtedly (adv) means Without any doubt; certainly. Example: “The mountain views were undoubtedly worth the long, tiring walk up the hill.”
adv
1
Without any doubt; certainly.
"The mountain views were undoubtedly worth the long, tiring walk up the hill."
"“It’s been a long process and I’ve come close to giving up along the way, but this is undoubtedly the craziest archaeological excavation I’ve yet been part of,” Bloch said in the news release."
— Amarachi Orie, Archaeologists discover true identity of Costa Rica shipwrecks long thought to be pirate ships (2025)
"He declared that these drastic steps would undoubtedly inconvenience a good many people, but the alternative was bankruptcy of the Ulster Transport Authority and the breakdown of public transport services."
— , Transport in Ulster (1956)
"The cane was undoubtedly of foreign make, for it had a solid silver ferrule at one end, which was not English hall–marked."
— Baroness Orczy i.e, The Ayrsham Mystery (1904)
"This is undoubtedly the best meal I've had all year."
"She is undoubtedly the most qualified candidate for the job."
How to use undoubtedly
Learner’s notesIn plain EnglishUsed to say something is certainly true, with no room for doubt.
Common pairings
undoubtedly the best
undoubtedly true
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Word forms
- Comparative
- more undoubtedly
- Superlative
- most undoubtedly
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The mountain views were _____ worth the long, tiring walk up the hill.
Etymology
From Middle English undoutedly, built from undoubted plus -ly.
Synonyms
View more →Antonyms
Related words
Rhymes for undoubtedly
wickedly
allegedly
hurriedly
decidedly
assuredly
excitedly
repeatedly
reportedly
admittedly
supposedly
unexpectedly
wholeheartedly
See all rhymes for undoubtedly →
Frequently asked questions
What does “undoubtedly” mean?
The word “undoubtedly” means without any doubt; certainly. In plain terms, used to say something is certainly true, with no room for doubt.
How do you pronounce “undoubtedly”?
“Undoubtedly” is pronounced uhn-DOW-tihd-lee (/ʌnˈdaʊtɪdli/ in IPA).
How do you use “undoubtedly” in a sentence?
Here is “undoubtedly” used in a sentence: “This is undoubtedly the best meal I've had all year.”
What part of speech is “undoubtedly”?
“Undoubtedly” is an adverb.
Where does the word “undoubtedly” come from?
The word “undoubtedly” comes from Middle English. From Middle English undoutedly, built from undoubted plus -ly.
Is “undoubtedly” a common word?
“Undoubtedly” is a fairly common word in modern English, usually learned at around the B2 level.
What is the difference between "undoubtedly" and "probably"?
"Undoubtedly" expresses full certainty with no room for doubt, while "probably" signals likelihood but leaves open the chance of being wrong. Choosing "undoubtedly" makes a statement far stronger than "probably."
What is the difference between "undoubtedly" and "doubtless"?
Both mean without doubt, but "undoubtedly" is more emphatic and common in modern writing, while "doubtless" can sometimes carry a hint of assumption, closer to "presumably." In most contexts they are interchangeable, as in "she will undoubtedly succeed."
Where should "undoubtedly" go in a sentence?
As an adverb, "undoubtedly" is flexible: it can open a sentence ("Undoubtedly, he was right"), sit before the main verb ("he undoubtedly knew"), or follow a form of "be" ("she was undoubtedly correct"). Placing it next to the idea it emphasises usually reads most naturally.
Is "undoubtedly" formal or informal?
"Undoubtedly" suits both formal and everyday writing, but it is especially common in academic and persuasive contexts where a writer wants to signal certainty. In casual speech, people often prefer shorter words like "definitely" or "for sure."
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