of: a particle (or rigid body) in uni-axial rotation about a single fixed axis of rotation
is: a vector, usually represented by the symbol 
whose magnitude is the angular speed 
about that axis, and whose direction is along the axis, in the sense given by the right-hand grip rule (i.e. if the fingers of the right hand are curled in the direction of rotation of the body, then the extended thumb points in the direction of the angular velocity). [P2.7, P2.8]
satisfies: the relation 
where 
is the velocity and 
the position vector of the particle (or of any point in the rigid body) measured from an origin O on the axis of rotation. [P2.7]
has as its SI unit: 
(i.e. radian per second).
Copyright 1997, The Open University