v. To handle incorrectly, to make a mistake in handling a thing or situation.
the GNU version of the Collaborative International Dictionary of English
v. To handle ill or wrongly; to maltreat.
The Century Dictionary and Cyclopedia
To maltreat.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
v. manage badly or incompetently
v. make a mess of, destroy or ruin
Word Usage
"The Department of Transportation issues statistics each month on the rate at which airlines "mishandle" luggage -- that is, don't deliver it to you with your flight."