utility program

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A program that performs a specific task related to the management of computer functions, resources, or files, as password protection, memory management, virus protection, and file compression.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun computing any of a large range of software, often included with the operating system of a mainframe or personal computer, that runs specific tasks associated with the computer or its environment

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun (computer science) a program designed for general support of the processes of a computer