Lew Ritter, 83, a clothier in Westwood and Beverly Hills since 1951 and before that a singer and dancer in vaudeville. Ritter began in the menswear business in 1937 and in the Los Angeles area developed a reputation for traditional clothing with an Ivy League flavor. His clients came to include Frank Sinatra, Zubin Mehta, Walter Matthau, Jack Kent Cooke and other celebrities. In 1984 he sold the Wilshire Boulevard business, which continues to operate under his name. In Santa Monica on Nov. 20 after a stroke.