Is it ensure, insure, or assure?
perhaps corruption of potato
slang, often used with 'sweet'
[1921+; perhaps fr a play on sweet potato suggested by sweetheart and potato as used, like tomato, to mean a person]
Abstaining from liquor; teetotal, at least temporarily: Monty didn't drink, and Clifton James went on the wagon
[1904+; first attested as on the water cart in 1902]