Definitions for "Thorough"
Thorough is a name given by the Earl of Stafford to a scheme of his to establish absolute monarchy in England. Although "Thorough" is largely attributed to the Earl of Strafford, it's implementation can also be accredited to the Archbishop of Canterbury William Laud.
painstakingly careful and accurate; "our accountant is thorough"; "thorough research"
very thorough; exhaustively complete; "an exhaustive study"; "made a thorough search"; "thoroughgoing research"
Keywords:  furrow, ridges, drain, off, surface
A furrow between two ridges, to drain off the surface water.