(HOF) A function that can take one or more functions as argument and/or return a function as its value. E.g. map in (map f l) which returns the list of results of applying function f to each of the elements of list l. See also curried function.
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Nearby terms: High-Definition Multimedia Interface « high density « Higher Education National Software Archive « higher-order function » higher-order macro » High-level Data Link Control » high-level language