Coventry is not a manufacturer of dinnerware, as it would appear to be. The term "Coventry" refers to a type of dinnerware, and it is manufactured by a variety of companies, the most notable of which is PTS America, which offers an entire line under the Coventry name.
Though the line made by PTS America is most likely what is being referred to by the term "Coventry," there have been other manufacturers to produce patterns under that name. Such manufacturers include Mikasa, Noritake, Royal Doulton, and Royal Winchester. The term Coventry is most likely derived from the name of a place, possibly in ancient England or one of the New England states.