spin

spin

noun \ˈspin\

Definition of SPIN

1

: a quantum characteristic of an elementary particle that is visualized as the rotation of the particle on its axis and that is responsible for measurable angular momentum and magnetic moment

2

: the angular momentum which is associated with spin, whose magnitude is quantized, and which may assume either of two possible directions; also : the angular momentum of a system of elementary particles derived from their spins and orbital motions—see spin echo, spin label