Indubitable
/ɪnˈduːbɪtəbəl/noun
Impossible to doubt; unquestionably true or certain.
Did you know?Indubitable comes from Latin dubitare, “to doubt,” which is also the root behind “dubious,” so English split one ancient root into both certainty and suspicion.
Etymological Timeline
Proto-Indo-European
PIE
*dwo-
“Two; split into two, implying uncertainty or division.”
Latin
Latin
dubitare
“To waver, hesitate, or doubt.”
Late Latin
Latin
indubitabilis
“Not doubtful; certain.”
Old French
Old French
indubitable
“Undoubtable, certain.”
14th–15th Century
English
indubitable
“Not open to doubt; beyond question.”
Modern English
English
indubitable
“Absolutely certain; incapable of being doubted.”