The crossword solution for the term 'Kind of Mug' is TOBY, which is a four-letter word. TOBY mugs are a type of ceramic mug that originated in England during the 18th century. They are typically made from earthenware and have a handle on one side. TOBY mugs are often decorated with a figure of a man wearing a tricorn hat, hence the name 'TOBY.' They are usually used for drinking beer or ale, but can also be used for other beverages.