A Snap Turn, also sometimes referred to as Click Turn, Incremental Turn, or Blink Turn, is a movement style some VR creators offer in their VR content. In an effort to reduce potential motion sickness, when the user attempts to turn their character through the use of a button or some other control, their character will "instantly" turn by a pre-determined amount. Often a value like 15 degrees, 30, 45, or 90 degrees.
The turn may happen with an instant view shift, or the view may turn gradually but extremely quickly (to avoid motion sickness), or Vignetting may be used.
In some VR content, this is a feature that can be turned on or off, or adjusted as to how many degrees and how quickly the turn will occur.