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A phase-point
(r₁,...,r_3N,p₁,...,p_3N)
is a point in the 6N dimensional phase-space.

A configuration

(r₁,...,r_3N)
is a point in the 3N dimensional configuration space.

A trajectory

(r₁(t),...,r_3N(t),p₁(t),...,p_3N(t))
is a continuous solution to the equation of motion.

An orbit

(r₁(nh),...,r_3N(nh),p₁(nh),...,p_3N(nh))
where n=1...N, and h is a timestep. The orbit is a series of points on the trajectory.

It should be obvious that the dynamics is a mapping

(r₁(nh),...,r_3N(nh),p₁(nh),...,p_3N(nh))

(r₁((n+1)h),...,r_3N((n+1)h),p₁((n+1)h),...,p_3N((n+1)h))

f(r₁,...,r_3N,p₁,...,p_3N)
is a function defined over a trajectory or over an orbit.