Doubtless
Doubtless adverb - Without any question.
Efficiently and doubtless are semantically related. In some cases you can use "Efficiently" instead an adverb "Doubtless".
Efficiently
Efficiently adverb - With efficiency; in an efficient manner.
Doubtless and efficiently are semantically related. Sometimes you can use "Doubtless" instead an adverb "Efficiently".
Nearby Words: efficient, efficiency
Cite this Source
Efficiently and Doubtless. (2016). Retrieved 2026, July 21, from https://thesaurus.plus/related/doubtless/efficiently
Doubtless & Efficiently. N.p., 2016. Web. 21 Jul. 2026. <https://thesaurus.plus/related/doubtless/efficiently>.
Efficiently or Doubtless. 2016. Accessed July 21, 2026. https://thesaurus.plus/related/doubtless/efficiently.
Google Ngram Viewer shows how "doubtless" and "efficiently" have occurred on timeline