(programming) A file, usually in the form of source code, that is automatically included in another source file by the compiler. / (programming) A file that contains declarations but no implementations.

(sports) A pair of games played one after another between the same teams. / A pair of sporting events, one after the other, at a single venue.

plural of header file

(sports) Three games played one after another between the same teams. / Three sporting events, one after the other, at a single venue.

(programming) Synonym of include guard

(electronics) A type of electrical connector, consisting of one or more rows of male pins evenly spaced apart.

plural of header guard

(possibly dated) A native or resident of Gay Head (now Aquinnah), a town on Martha's Vineyard with a significant Wampanoag population.

Four sporting events, one after the other, at a single venue. / Four sporting events, one after the other, broadcast on the same television channel.