Source : Webster's Revised Unabridged Dictionary (1913)

Pandiculation \Pan*dic`u*la"tion\, n. [L. pandiculari to stretch
   one's self, fr. pandere to spread out.]
   A stretching and stiffening of the trunk and extremities, as
   when fatigued and drowsy.

Source : WordNet®

pandiculation
     n : yawning and stretching (as when first waking up)