Static stability

The initial response that an airplane displays after its equilibrium is disrupted.

Aviation Maintenance Technician Handbook — General, p. G-10

Also defined in 2 more sources

The characteristic of an aircraft that causes it to return to straight and level flight after it has been disturbed from that condition.

Aviation Maintenance Technician Handbook — Airframe, p. G-34

The initial tendency an aircraft displays when disturbed from a state of equilibrium.

Pilot's Handbook of Aeronautical Knowledge, p. G-29