One of the ultimate teasable names, an Irish saint's name now associated with the oversized comic-strip dog. Scottish adventurer Bear (born Edward) Grylls took up the challenge when he used it for his son.
Marmaduke, title Great Dane in comic strip and movie
Marmaduke Brooker, character from the TV series "Carpoolers"
Marmaduke Duke, Scottish rock duo
Marmaduke "Chuffy" Chuffnell, 5th Baron Chuffnell, character in P. G. Wodehouse's Jeeves novels
Marmaduke, character in the Demon Princes series by JackVance
Marmaduke (Duke) Rosenly, full name of collie dog character in "The Space Gypsy Adventures"