Abbott and Costello were a famous comedy DUO who rose to fame in the 1940s. They were known for their iconic 'Who's on First?' routine, which made them one of the most popular DUOS of all time. The term 'Abbott and Costello' can be summarized by four crossword solutions: DUOS (4 letters), PAIR (4 letters), WHO (3 letters), DUO (3 letters), and TEAM (4 letters). All of these words refer to two people working together, which is what Abbott and Costello did.