Neither tomatoes nor cucumbers are vegetables — they're fruits. The debate about whether a tomato is a fruit or not actually made it to the Supreme Court in 1883 in Nix v Hedden. The tomato was declared to be botanically a fruit but for all other purposes a vegetable.
More on fruits and vegetables:
- The biggest difference between fruits and vegetables is the presence of seeds. Tomatoes, cucumbers, pumpkins and peppers all have seeds, so they are all technically fruits.
- The strawberry is actually not a berry. It is closely related to the rose family, and the edible berry part is actually what is known as a "false fruit." The true berry of the strawberry is the little black specks that contain the seeds.
- Eggplants and avocados are technically classified as berries.