noun
carton
KAR-tun/ˈkɑːrtn/
A lightweight cardboard or plastic container for goods or liquids.
The open carton has lightweight cardboard sides and folded flaps.

Etymology
The paper root and enlarging suffix produced a word for substantial paper or pasteboard. The name then shifted from the material to the packaging boxes made from it.
In context
this is a snail's shell it's absolutely massive in this egg carton I found some shells in these pizza boxes