What is the difference between undoubtedly and indubitably?

Answer 1

There is no difference, it's the same meaning. They're synonyms of each other.

Example: Jim is undoubtedly/indubitably a homosexual.

Answer 2

Both words mean "without doubt" or "unquestionably," but "undoubtedly" is more commonly used and accepted in standard English, while "indubitably" is considered more formal and less commonly used. Additionally, "undoubtedly" is used more in everyday conversation and writing, while "indubitably" is more likely to be found in academic or literary contexts.