Source : Webster's Revised Unabridged Dictionary (1913)

Vacuolation \Vac"u*o*la"tion\, n. (Biol.)
   Formation into, or multiplication of, vacuoles.

Source : WordNet®

vacuolation
     n : the state of having become filled with vacuoles [syn: {vacuolization},
          {vacuolisation}]