Inexcusably
Pronunciation : In`ex*cus"a*bly
Part of Speech : adv.
Definition : Defn: With a degree of guilt or folly beyond excuse or justification. Inexcusably obstinate and perverse. Jortin.
Source : Webster's Unabridged Dictionary, 1913
Merriam-Webster's Everyday Language Reference Set: Includes: The Merriam-Webster Dictionary, The Merriam-Webster Thesaurus, and The Merriam-Webster Vocabulary Builder