1) By all odds 2) Definitely 3) Emphatically 4) In spades 5) Unquestionably 1) Clearly 2) Definitely 3) Emphatically 4) Extremely 5) Tremendously 6) Unmistakably 
Ridden by Bill Hartack, Decidedly set a new Churchill Downs track record for 1¼ miles in winning the 1962 Derby. In the second leg and third legs of the U.S. Triple Crown series, the Preakness and Belmont Stakes, he was unplaced. In 1963 Decidedly won five of thirteen starts and set a new Keeneland Race Course record for 11/16 miles in winning th...
• (adv.) In a decided manner; indisputably; clearly; thoroughly.
De·cid'ed·ly adverb In a decided manner; indisputably; clearly; thoroughly. 
[adv] - without question and beyond doubt
unquestionably 1 emphatically adverb without question and beyond doubt; `it was decidedly too expensive`; `she told him off in spades`; `by all odds they should win`