What is "rubberduck"

Rubberduck (real name Byrd Rentals) is a fictional character in the DC Comics universe, an anthropomorphic duck. Rubberduck is a superhero who lived on the otherdimensional world of Earth-C (now Earth-26), an alternate Earth populated by sentient animals. His first appearance was in a special insert in The New Teen Titans #16 (February 1982).

Rubberduck's alter-ego's name, "Byrd Rentals," is a play on actor Burt Reynolds; being Burt Reynolds' Earth-C/26 counterpart, Byrd Rentals' career roughly matched that of Burt Reynolds', starring in films such as The Longest Yarn (a play on The Longest Yard) and Smoke-Eye and the Panda (a play on Smokey and the Bandit).