over a set

over a set

[¦ō·vər ə ′set]
(mathematics)
A map ƒ from a set A to a set L is said to be over a set B if B is a subset of both A and L and if the restriction of F to B is the identity map on B.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.