(literally) A support structure comprising joined parts or conglomerated particles and intervening open spaces of similar or larger size.

(literally) The arrangement of support beams that represent a building's general shape and size.

(figurative) The larger branches of a tree that determine its shape.

(figurative) A basic conceptual structure.

(software engineering) A reusable piece of code (and, sometimes, other utilities) providing a standard environment within which an application can be implemented.

(grammar) An established and structured system of rules and principles used for analyzing and describing the structure of a language.