Answers:
obesity is individual grossly overweight, i believe the threshold is over 10% of your bodyweight overweight. It can be measured using a body mass indicator BMI scale, survey and you can find an easy calculator.
Other Answers:
its when you achieve really over weight
Go here to cram more and to answer your question.
http://www.obesity-online.com/
its when you are overweight..and it "get started" by eating to much fatty foods..and stuff explicitly not good for you.
OBESITY IS BEING OVER WEIGHT AND IT IS STARTED BY EATING TO MUCH JUNK FOOD AND NOT GETTING ENOUGH ECXERCISE. I HOPE YOU R NOT OBESE. IF YOU R TRIE DIET AND EXCERCISE