window function

window function (plural window functions)

1. (databases) A function that performs a calculation using values from several rows, but does not group them into a single row.

   Synonym: analytic function

   Coordinate term: aggregate function

2. (signal processing, statistics) A function that limits a signal to a restricted portion of time or frequencies.

   Hyponym: boxcar function

•   window function on Wikipedia.Wikipedia
•   window function (SQL) on Wikipedia.Wikipedia