Mov·a·ble a.
  1. Capable of being moved, lifted, carried, drawn, turned, or conveyed, or in any way made to change place or posture; susceptible of motion; not fixed or stationary; as, a movable steam engine. [Also spelled moveable.]
  Syn: -- transferable, transferrable, transportable.
  2. Changing from one time to another; as, movable feasts, i. e., church festivals, the date of which varies from year to year.
  Movable letter Heb. Gram., a letter that is pronounced, as opposed to one that is quiescent.
  Movable feast Ecclesiastical, a holy day that changes date, depending on the lunar cycle.  An example of such a day is Easter.