Botanically vegetables are any part of the plant that aren't seed bearing structures. Fruit are said seed bearing structures. There is a clear dividing line between the 2.
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Culinary its based on the flavor and usage more than anything to do with what part it is.
No word is originally a botanical term. Deprecated definitions from Middle English are not a valid argument for defining the objective categorization of an item.
I guess originally is a bad way to put it but outside of botany in some fields where plants are used in a culinary respect. vegetable is a blanket term for whatever plant matter we eat. And unsurprisingly humans were culinarily inclined before we were botanically inclined so we had put a blanket term over things either inedible vegetation or vegetables.
Notice in my original statement I already covered culinary. In a culinary sense what is a vegetable and what is a fruit is almost entirely based on what it tastes like. A good example is the tomato. Culinarily it isn't a vegetable. It's a fruit because of its content, taste, and use in cooking.
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Culinary its based on the flavor and usage more than anything to do with what part it is.
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