Max Feldberg, 90, co-founder with his brother Morris of the pioneering Zayre discount department store chain. The Feldbergs started their first stores in Boston and Hyannis, Mass., in 1956. They guided the growth of Zayre Corp. into one of the nation’s biggest retail chains, with 1,187 outlets in 43 states and the District of Columbia. The corporation also operates HomeClub, T. J. Maxx, Hit or Miss, Chadwick’s of Boston and BJ’s Wholesale Club. The Feldberg brothers fled to the United States from Russia in the early 1900s to escape conscription in the czar’s army and settled in Chelsea, Mass., with their mother. The brothers began a small hosiery business in Chelsea in 1919. The business later branched out with the acquisition of retail apparel chains in New England and Greater New York. They were among the first to open self-service, discount stores outside the downtown retail areas. They took the name Zayre from a phonetic spelling of the Yiddish word meaning “very,” as in “very good.” Morris Feldberg died in 1969, Max in Boston on Tuesday.