https://www.boldmethod.com/blog/quizzes/2022/08/six-questions-to-test-your-v-speed-knowledge/

Vs0
The beginning of the White Arc is the power off Stalling Speed with gear and full flaps extended, also known as Vs0. The Vs0 (Velocity Stall 0) represents the Stalling Speed of the aircraft configured for landing. (i.e. Gear Down and Flaps Down) An easy way to remember this is to think of the Velocity (V) of Stall (s) with everything hanging Out (0) or Vs0.

Rappel: https://learntofly.ca/airspeeds-v-speeds-vx-vy-vs-vs1-va-vno-vne-vfe/