mechanical engineering

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

• noun The branch of engineering that encompasses the generation and application of heat and mechanical power and the design, production, and use of machines and tools.

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

• noun engineering The subfield of engineering concerned with designing and building machines and mechanical systems

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

• noun the branch of engineering that deals with the design and construction and operation of machinery