1. A plant with edible parts or any plant whose fruit, seeds, roots, tubers, bulbs, stems, leaves, or flower parts are used as food; such as, the tomato, bean, beet, potato, onion, asparagus, spinach, or cauliflower.
2. A member of the plant kingdom or vegetable kingdom.
3. A term which is used to describe someone in whom the usual mental and physical functions are severely reduced or absent, often as a result of injury to the brain; in a vegetative state.
4. Someone who is regarded as lacking in vitality, alertness, or drive.
5. Etymology: "living and growing as a plant", from Old French "living, fit to live", from Medieval Latin vegetabilis, "growing, flourishing", from Late Latin vegertabilis, "animating, enlivening", from Latin vegertare, "to enliven", from vegetus, "vigorous, active", form vegere, "to be alive, to be active, to quicken".

In 1582, it was recorded for the first time that the adjective use of vegetable became familiar to English, "having to do with plants".

In a work of the same date appears the first instance of vegetable as a noun, meaning "a plant".

It was not until the 18th century that the noun and adjective were used more restrictively to refer specifically to certain kinds of plants that are eaten.