THERE IS a theory that the phrase couch potato derived from calling the television a boob-tube. Viewers were boob-tubers, and the shift from tuber to potato came naturally. Boob-tube was then freed to become a constrictive item of women's clothing.

The term couch potato was coined by Tom Iacino in the late 1970s, but popularised in two books by Robert Armstrong and Jack Mingo: Dr Spud's Etiquette for the Couch Potato (1982) and The Official Couch Potato Handbook (1983). A couch potato is essentially male, though he may call on the services of a couch tomato to maintain supplies of food and drink.

Related words include: Couch-potatoing (first seen in 1987) and telespud (also 1987). The more specialised term videot never seems to have caught on.