Source : Webster's Revised Unabridged Dictionary (1913)

Fontanelle \Fon`ta`nelle"\, n. [F.] (Anat.)
   Same as {Fontanel}, 2.

Source : WordNet®

fontanelle
     n : any membranous gap between the bones of the cranium in an
         infant or fetus [syn: {fontanel}, {soft spot}]