jet lag

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

• noun A temporary disruption of bodily rhythms caused by high-speed travel across several time zones typically in a jet aircraft.

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

• noun A physical condition caused by crossing time zones during flight; often the result of disruption to the circadian rhythms of the body.

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

• noun fatigue and sleep disturbance resulting from disruption of the body's normal circadian rhythm as a result of jet travel