Coventry Blue. Thread principally used for purposes of embroidery,of a vivid blue, very popular in England in the 16th century, and for many years manufactured at Coventry, whence the name. In a letter attributed to Shakespeare, with the long-winded title of A Compendious and Brief Examination of Certain Complaints of divers of our Countrymen in these our days, on the decay of Towns, the writer says: "I have heard say that the chiefe trade of Coventry was heretofore in making blue threde, and then the town was riche, even upon that trade in manner only; and now our threde comes all from beyond the sea; therefore that trade is now decayed, and thereby the town likewise."