doubtlessly

D2O1U1B3T1L1E1S1S1L1Y4

adverb

Without question; indubitably.

“There are doubtlessly more insects than mammals.”

UncommonScrabble 17

Meanings

adverbdoubtlessly (comparative more doubtlessly, superlative most doubtlessly)

comparative more doubtlessly · superlative most doubtlessly

  1. proscribedsometimesWithout question; indubitably.

    There are doubtlessly more insects than mammals.

  2. obsoleteWithout feeling doubt, without misgivings.

    Some powers diuine, or els infernall, mixt Their angry ſeedes at his conception: For he was neuer ſprong of humaine race, Since with the ſpirit of his fearefull pride, He dares so doubtleſly reſolue of rule.

    c. 1587–1588 (date written), [Christopher Marlowe], Tamburlaine the Great. […] The First Part […], 2nd edition, part 1, London: […] [R. Robinson for] Richard Iones, […], published 1592, →OCLC; reprinted as Tamburlaine the Great (A Scolar Press Facsimile), Menston, Yorkshire; London: Scolar Press, 1973, →ISBN, Act II, scene vi

Synonyms & antonyms

adverbwithout doubt; certainly

Synonym sets from Open English WordNet, CC BY 4.0.

Origin

  1. Middle Englishdoutelesly
  2. Englishdoubtlessly

From Middle English doutelesly, dowtelesly, equivalent to doubtless + -ly.

Full word history & related roots →
Cite this entry
APA

doubtlessly. (n.d.). In WatkinsX Dictionary. Retrieved November 2, 2026, from https://dictionary.watkinsx.com/word/doubtlessly

MLA

“doubtlessly.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/doubtlessly. Accessed November 2, 2026.

Chicago

WatkinsX Dictionary, s.v. “doubtlessly,” accessed November 2, 2026, https://dictionary.watkinsx.com/word/doubtlessly.

Source: doubtlessly on Wiktionary, CC BY-SA 4.0.