Physics, Chemistry. 1  a wave function describing the state of a single electron in an atom (atomic orbital) or in a molecule (molecular orbital) 2  the electron in that state.
DEFINITION of 'Yo-Yo'. Slang for a very volatile market. A yo-yo market will have no distinguishing features of either an up or down market, taking on characterstics of both. Security prices in a yo-yo market will swing very high to low over a given period of time, making it difficult for buy and hold investors to profit. Next Up.
But when people yo-yo diet, the body may not have time to make those adjustments. Another theory, developed after a trial using mice, suggests yo-yo dieting may have an impact on DNA. We found that mice exposed to weight cycling behaviours ended up with damage to their DNA, notes Rasla.