adj. 1. Exhaustively complete: a thorough search. 2. Painstakingly accurate or careful: thorough research. 3. Absolute; utter: a thorough pleasure. [Middle English thorow, through, thorough, from Old English thuruh, from end to end, through; see terə-2 in the Appendix of Indo-European roots.] thorough·ly adv. thorough·ness n. |
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