or copy someone else's idea or product and try to pass it off as your original idea. (example 1)
Can also be used as a confession when one is willing to admit they got the idea elsewhere and does not wish to take credit from the inventor (example 2)
Person 1: "Stephanie's homemade purse is so cute! How creative!
Person 2: "she totally gagaed that off Pintrest..."
Person 1: "You made that! That is so ingenious!"
Person 2: "Oh I gagaed this from some girls blog. It has instructions and everything on how to make your own."