The Collaborative International Dictionary
Coventry blue
Coventry \Cov"en*try\ (k?v"en-tr?), n. A town in the county of Warwick, England.
To send to Coventry, to exclude from society; to shut out from social intercourse, as for ungentlemanly conduct.
Coventry blue, blue thread of a superior dye, made at Coventry, England, and used for embroidery.