adjective
- not called in question; accepted as beyond doubt; undisputed.
adverb
- certainly or definitely; unquestionablyhe is undoubtedly talented
- (sentence modifier) without doubt; certainly or indisputablyundoubtedly there will be changes
adjective
- beyond doubt; certain or indisputable
adj.mid-15c., from un- (1) “not” + past participle of doubt (v.).