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.
wikiHow to Make a Yo Yo. Community Q&A. One of the simplest and most common toys is the yo yo. A round piece of carved wood or plastic, and a piece of string has entertained people for centuries. But it's practically impossible to make a yo yo without an expensive piece of machinery called a lathe... or is it?