An example of this is the term groovy which is a relic of 1960's and 70's American hippy slang. Nevertheless, for a slang term to become a slang term, people must use it, at some point in time, as a way to flout standard language.
Cycling is a highly effective form of exercise. It requires a lot of energy, builds lean muscle mass, and improves your strength, cardio capacity and endurance. However, cycling won't specifically burn belly fat. It will certainly help to reduce your overall body fat, but since spot reduction is a myth, you will have to be patient for your belly fat to burn off with the rest of your fat.
While Pilates offers an array of health benefits, including core stability developments, improved posture and balance, increased flexibility and a decreased risk of lower back pain, it will not help you lose fat in the belly. It isn't possible to spot reduce, which means you can't target fat loss at a particular area. To lose fat in the stomach, you'll have to engage in higher intensity exercises that burn more calories, though you may continue to do Pilates to tone muscles for more defined abs.