[uncountable, countable] how heavy somebody/something is, which can be measured in, for example, kilograms or pounds It is about 76 kilos in weight. Bananas are sold by weight. In the wild, this fish can reach a weight of 5lbs. She is trying to lose weight (= become less heavy and less fat). He’s put on/gained weight(= become heavier and fatter) since he gave up smoking. Sam has a weight problem (= is too fat). No more for me. I have to watch my weight.