I. ˈthər-(ˌ)ō, sometimes ˈthȯr-; ˈthə-(ˌ)rō preposition
Etymology: Middle English thorow, from Old English thurh, thuruh, preposition & adverb
Date: before 12th century
archaic : through
II. adverb
Date: before 12th century
archaic : through
III. adjective
Date: 15th century
1. : carried through to completion : exhaustive
a thorough search
2.
a. : marked by full detail
a thorough description
b. : careful about detail : painstaking
a thorough scholar
c. : complete in all respects
thorough pleasure
d. : having full mastery (as of an art)
a thorough musician
• thor·ough·ly adverb
• thor·ough·ness noun