toby jug, small pottery pitcher or mug modeled in the form of a jolly, stout man wearing a cocked hat, a corner of which serves as pourer. The jug is also called fillpot, both names taken from Toby Fillpot, inebriate character in the 18th-century song Little Brown Jug. Popular in England and America of that day, the toby jug has become a collector's piece.