1. existing and ready for action, but not active.
2. electric tension or pressure.
- action p. — see action potential.
- after-p. — the period following termination of the spike potential.
- membrane p. — see membrane potential.
- resting p. — the potential difference across the membrane of a normal cell at rest.
- spike p. — the initial, very large change in potential of an excitable cell membrane during excitation.
- zeta p. — a net negative charge.
