Also found in: Dictionary, Thesaurus, Encyclopedia, Wikipedia.


The psychophysiologic effect of zero gravity, as experienced by someone falling freely in a vacuum (for example, astronauts in a stable orbit). A temporary state of simulated weightlessness can be achieved during powered flight within the earth's atmosphere by traversing an inverted parabolic curve where gravitational pull and centrifugal force cancel each other out.
Farlex Partner Medical Dictionary © Farlex 2012
A state in which there is no gravitational effect on a body or material
Physiologic effects Bone mineral loss, altered blood chemistries, weakened immune system, variable heart rate, arrhythmias, loss of skeletal and cardiac muscle mass and strength, increased urinary loss of nitrogen and phosphorus, motion sickness, and redistribution of fluids that are normally pooled in the lower torso and legs, resulting in a ‘fat face’
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.
References in periodicals archive ?
The shape of the heart will change in weightlessness, which is demonstrated by the cardiac sphericity and the Geometric Aspect Ratios (GAR, length to width quotient).
The purpose of developed space robotic system weightlessness test bench is servoing of robotic system during different operations.
NASA Commentator Lori Meggs at the Marshall Space Fight Center speaks with Jojo Sayson, a co-investigator for the Intervertebral Disc Damage study, about research underway to understand the causes of back pain suffered by crew members while working in weightlessness on the International Space Station.
Once in space, passengers will experience a short period of zero gravity (or weightlessness), and can get out of their seats and float around the cabin.
"These ZeroG flights are a first step towards 'Space for All', giving everyone the chance to enjoy the weightlessness experienced by astronauts in space,"[euro]oCi said S3 chief executive Pascal Jaussi in a statement.
A specially-designed "reduced gravity aircraft" is used to produce the sensation of weightlessness, by repeatedly climbing at a steep angle towards its maximum altitude before entering a nosedive.
The Misguided Search for the Political: Social Weightlessness in Radical Democratic Theory
Flying with Zero Gravity Corp., model Kate Upton flipped, floated and modeled in true weightlessness as if in outer space for Sports Illustrated's 50th anniversary Swimsuit issue.
In a show about weightlessness, that's a serious problem.
The 61-year-old experienced weightlessness on a one-hour commercial space flight and admitted it was "pretty mind-blowing".
The students were taught all about a Space Shuttle mission, from take-off to landing, and also about how the human body adapts to weightlessness.