When you upload or share pictures on the internet while hiding the fact that you are fat. Taking pictures from the neck up because you are overweight or taking pictures hiding the "pooch" with a purse or handbag, or any object including other people. Taking pictures sideways because your are overweight and uploading on social media. Basically any attempt to hide being over weight via pictures. Using slimmer pictures or avatars of yourself than you are as a socila media profile picture.
All her pictures are from the neck up, she's probably fat fishing.
She only take pictures with her purse covering her stomach, shes probably fat fishing.
I saw her pictures and thought she was slim, but when we met she was fat and said those were her older pictures, I got fat fished.
Commonly used to describe when individuals (most often females) take pictures at specific angles or lighting to use for online dating/hookups and social media that give the appearance that they aren't fat, when in actuality, they are fat.