Someone who contains; something that contains.

An item in which objects, materials or data can be stored or transported.

(transport) A very large, typically metal, box used for transporting goods.

(by extension) Someone who holds people in their seats or in a (reasonably) calm state.

(computing) A file format that can hold various types of data.

(object-oriented programming) An abstract data type whose instances are collections of other objects.

(computing, graphical user interface) Any user interface component that can hold further (child) components.

(computing) A bundle consisting of operating system, application code and dependencies to be run sandboxed inside a virtualized environment; the environment itself.