An I-beam suspended from a crane.
I-beam definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
a steel beam which in cross section has the shape of an I
I-beam definition by American Heritage Dictionary
A steel joist or girder with short flanges and a cross section formed like the letter I.