the GNU version of the Collaborative International Dictionary of English
adj. Not doubted; not called in question; indubitable; indisputable.
The Century Dictionary and Cyclopedia
Not doubted; not called in question; indubitable; indisputable.
Not filled with doubt, apprehension, fear, or the like; hence, confident; bold; fearless; redoubted.
Not being an object of doubt or suspicion; unsuspected.
Undoubtedly.
Word Usage
"It reflects part of reality-namely the undoubted reversal of emphasis from war limited in space, scope, and objectives to global strife for grandiose ends, using means beyond those permitted before 1914."