pack (something) to the gunwales

To fill something as much as is possible; to pack something as full as it can be or to the very top. A gunwale (alco called a "gunnel") is the uppermost part of the side of a boat or fortification. I packed the car to the gunwales, so if you want to bring anything else, you'll have to hold it on your lap. Why do you insist on packing this closet to the gunwales? Every time I open it, an avalanche of stuff comes falling out!

packed to the gunwales

As full as possible; filled up to the very top. A gunwale (alco called a "gunnel") is the uppermost part of the side of a boat or fortification. The car is packed to the gunwales, so if you want to bring anything else, you'll have to hold it on your lap. Why do you insist on keeping this closet packed to the gunwales? Every time I open it, an avalanche of stuff comes falling out!