Nix v. Hedden
Plaintiff Nix ran a large produce import company which included importing tomatoes. Congress passed the Tariff of 1883, which required a tax to be paid on vegetables, but not fruit.
Are tomatoes vegetables or fruits for tariff purposes?
Three different dictionaries all define fruit as the seed of plants or the part of plants that contains the seed. This definition describes a tomato.
Tomatoes are fruits botanically-speaking, just like cucumbers, squashes, beans, and peas all are. But in the common language of the people, all these are vegetables. You eat them with other vegetables or meat, not as dessert like fruits generally are.
This is like the recent attempt to classify beans as seeds. While botanically true, that is not how they are treated in practice by anybody. Both beans and tomatoes are used as vegetables. This is just common knowledge.
Tomatoes are vegetables.