indubious

From Latin indubius. See in- (“not”) +‎ dubious.

• IPA^(key): /ɪnˈdjuːbiəs/, /ɪnˈduːbiəs/

indubious (comparative more indubious, superlative most indubious)

1. Not dubious or doubtful; certain.
2. Not doubting; unsuspecting.
   • 1673, Gideon Harvey, A Discourse of the Plague:

     indubious confidence

• “indubious”, in Webster’s Revised Unabridged Dictionary, Springfield, Mass.: G. & C. Merriam, 1913, →OCLC.