quantal

quan·tal

adj \ˈkwänt-^əl\

Definition of QUANTAL

1

: of or relating to a quantum or to quanta (as of energy or a neurotransmitter) <quantal release of acetylcholine>

2

: being or relating to a sensitivity response marked by the presence or absence of a definite reaction <an all-or-none response to a stimulus is quantal>