DECIDEDLY
decidedly, unquestionably, emphatically, definitely, in spades, by all odds
(adverb) without question and beyond doubt; “it was decidedly too expensive”; “she told him off in spades”; “by all odds they should win”
Source: WordNet® 3.1
Etymology
Adverb
decidedly (comparative more decidedly, superlative most decidedly)
In a manner which leaves little question; definitely, clearly.
In a decided or final manner; resolutely.
Source: Wiktionary
De*cid"ed*ly, adv.
Definition: In a decided manner; indisputably; clearly; thoroughly.
Source: Webster’s Unabridged Dictionary 1913 Edition