spiral point
An equilibrium every nearby trajectory winds around infinitely often while approaching or leaving.
A spiral point (or focus) is an equilibrium of \mathbf{x}'=A\mathbf{x} with complex eigenvalues having nonzero real part -- trajectories wind around it infinitely often while spiraling inward (stable, real part negative) or outward (unstable, real part positive).
See also
Point table
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