Re: fill up on something =? stuff oneself with something
They don't necessarily mean the same, no. The person in question might have a voracious appetite and be able to eat a huge quantity of food without feeling full. If he stuffs himself, then he eats a lot but we don't know for sure that he is full. In BrE at least, to "stuff yourself" simply means "to eat a large quantity". Bear in mind, though, that saying "I'm stuffed" means "I'm full. I don't think I could eat another thing".
Originally Posted by JACEK1
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