Source : Webster's Revised Unabridged Dictionary (1913)

Thoroughly \Thor"ough*ly\, adv.
   In a thorough manner; fully; entirely; completely.

Source : WordNet®

thoroughly
     adv 1: in a complete and thorough manner (`good' is sometimes used
            informally for `thoroughly'); "he was soundly
            defeated"; "we beat him good" [syn: {soundly}, {good}]
     2: in an exhaustive manner; "we searched the files thoroughly"
        [syn: {exhaustively}]