Main Entry: quan·tum

Pronunciation: \ˈkwänt-əm\

Function: noun

Inflected Form(s): plural quan·ta \ˈkwänt-ə\

1 : one of the very small increments or parcels into which many forms of energy are subdivided <a molecule of rhodopsin in the human eye can cause a response to a single quantum of light>
2 : one of the small molecular packets of a neurotransmitter (as acetylcholine) released into the synaptic cleft in the transmission of a nerve impulse across a synapse