English edit

Etymology edit

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

Adverb edit

doubtlessly (comparative more doubtlessly, superlative most doubtlessly)

  1. (sometimes proscribed) Without question; indubitably.
    There are doubtlessly more insects than mammals.
  2. (obsolete) Without feeling doubt, without misgivings.
    • c. 1587–1588, [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:
      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.

Usage notes edit

Sometimes considered a redundancy, as doubtless (without the -ly suffix) functions as an adverb with an identical meaning. The synonyms indubitably, undoubtedly, and unquestionably all require the -ly suffix.

Translations edit