I Have Difficulty Swallowing Occasionally When Eating Or General. It

I have difficulty swallowing occasionally when eating or general. It takes a lot of effort and when eating food like steak, I have to drink water to help push the food down. My cousin has the same thing and I forgot what it was called, I think it started with "gastro", but I am not sure. He had an endoscopy and the doctor confirmed this. What is it called? What causes this?