What is Pseudo-periodic and aperiodic regimes?

In a series RLC circuit the resistor dissipates energy by Joule heating (Chapter 12): the free oscillations are damped. Two regimes, read off an oscilloscope:

• pseudo-periodic (small $R$): the circuit still oscillates inside a shrinking envelope, with a repeat time — the pseudo-period — close to $T_0 = 2\pi\sqrt{LC}$ when the damping is light;
• aperiodic (large $R$): the charge creeps back to zero without ever overshooting — no oscillation at all.

The exact mirror of the damped mechanical oscillator (Definition 28.12).