Princeton's WordNet(4.60 / 5 votes)Rate this definition: 1  operation(noun) the state of being in effect or being operative. 2  operation(noun) a business especially one run on a large scale. 3  operation(noun) a planned activity involving many people performing various actions.
Tomatoes are a nutrient-dense food, meaning they are jam-packed with nutrients, but don't have a lot of calories. Lipids, carbs and protein are the three types of macronutrients your body breaks down for energy. The primary macronutrient in tomatoes is carbohydrates, although they do have trace amounts of fat and protein.
A tomato is both a fruit and a vegetable, depending how (and why) you want to look at it. Botanically, it's the fruit of the tomato plant. For purposes of human consumption, though, it's primarily a vegetable. It's not generally eaten in the same way as a fruit like a banana or apple. It tends to be eaten more like a vegetable like onion or lettuce.