Adverb
Undoubtedly; unquestionably; in a manner to remove all doubt.
Source: Webster's dictionaryOrganic life, we are told, has developed gradually from the protozoon to the philosopher, and this development, we are assured, is indubitably an advance. Unfortunately it is the philosopher, not the protozoon, who gives us this assurance. Bertrand Russell
MAN, n. An animal so lost in rapturous contemplation of what he thinks he is as to overlook what he indubitably ought to be. Ambrose Bierce
No facts, however indubitably detected, no effort of reason, however magnificently maintained, can prove that Bach's music is beautiful. Edith Hamilton
If "rights" exist at all-and both feeling and usage indubitably prove that they do exist-they cannot be consistently awarded to men and denied to animals, since the same sense of justice and compassion apply in both cases. Henry Stephens Salt
The British and American literary worlds operate in an odd kind of symbiosis: our critics think our contemporary novelists are not the stuff of greatness whereas certain contemporary Americans indubitably are. Their critics often advance the exact opposite: British fiction is cool, American naff. Will Self
it was immediately and indubitably apparent that I had interrupted a scene of lovers Source: Internet