The term ONE FOR MY BABY SINGER is a reference to two singers, Lena Horne and Frank Sinatra. Lena Horne was an American singer, actress, and civil rights activist who had a successful career in Hollywood during the 1940s and 1950s. Her five-letter surname is 'HORNE'. Frank Sinatra was an American singer, actor, and producer who is one of the most popular and influential musical artists of the 20th century. His four-letter surname is 'LENA'.