Type of mathematical function

Wiktionary Word definitions in Wiktionary
adv. 1 In terms or by means of pieces; a piece at a time. 2 (context mathematics English) Throughout separate parts, but not necessarily throughout the whole

Wikipedia Word definitions in Wikipedia
In mathematics , a piecewise-defined function (also called a piecewise function or a hybrid function ) is a function which is defined by multiple sub-functions, each sub-function applying to a certain interval of the main function's domain (a sub-domain). ...