CLERK, in its original sense, as used in the civil law, one who had taken religious orders of whatever rank, whether "holy" or "minor." In English ecclesiastical law, a clerk was any one who had been admitted to the ecclesiastical state, and had taken the tonsure. The application of the word in this sense gradually underwent a change, and "clerk" became more especially the term applied to those in minor orders, while those in "major" or "holy" orders were designated in full "clerks in holy orders." After the Reformation the word "clerk" was still further extended to include laymen who performed duties in cathedrals, churches, etc., e.g., the choirmen, who were designated "lay clerks." Of these lay clerks or choirmen there was always one whose duty it was to be constantly present at every service, to sing or say the responses as the leader or representative of the laity. His duties were grad ually enlarged to include the care of the church and precincts, assisting at baptisms, marriages, etc., and he thus became the pre cursor of the later parish clerk. In a somewhat similar sense we find bible clerk, singing clerk, etc. The use of the word "clerk" to denote a person ordained to the ministry is now mainly legal.
From the fact that in mediaeval times learning was chiefly the province of the clergy, they were engaged in nearly all occupations requiring knowledge of writing combined with some education and hence the word "clerk" came to its present indefinite signi fication of a writer in the employment of some one else. Older and more specific use of the word is to be traced in clerk of the market, clerk of the petty bag, clerk of the peace, town clerk, etc.