1. (prep.) Through.

2. (a.) Passing through; as, thorough lights in a house.

3. (a.) Passing through or to the end; hence, complete; perfect; as, a thorough reformation; thorough work; a thorough translator; a thorough poet.

4. (adv.) Thoroughly.

5. (adv.) Through.

6. (n.) A furrow between two ridges, to drain off the surface water.