Meanings
adverbundoubtlessly (comparative more undoubtlessly, superlative most undoubtlessly)
comparative more undoubtlessly · superlative most undoubtlessly
- nonstandardSynonym of without a doubt.
“Now, little girl,” he says, with a fatherly smile (he'll soon be twenty-six), “tell me just what your difficulty is, and undoubtlessly we'll fix it up in a jiffy!”
1920, American Magazine, volume 90, page 70Synonyms: without a doubt
Synonyms & antonyms
adverbSynonym of without a doubt.
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Origin
Cite this entry
APA
undoubtlessly. (n.d.). In WatkinsX Dictionary. Retrieved November 3, 2026, from https://dictionary.watkinsx.com/word/undoubtlessly
MLA
“undoubtlessly.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/undoubtlessly. Accessed November 3, 2026.
Chicago
WatkinsX Dictionary, s.v. “undoubtlessly,” accessed November 3, 2026, https://dictionary.watkinsx.com/word/undoubtlessly.
Source: undoubtlessly on Wiktionary, CC BY-SA 4.0.