The Collaborative International Dictionary of English v.0.48:
Prior \Pri"or\, n. [OE. priour, OF. priour, prior, priur, F.
prieur, from L. prior former, superior. See Prior, a.]
1. (Eccl.) The superior of a priory, and next below an abbot
2. a chief magistrate, as in the republic of Florence in the
middle ages. --[RHUD]
Conventical prior, or Conventual prior, a prior who is at
the head of his own house. See the Note under Priory.
Claustral prior, an official next in rank to the abbot in a
monastery; prior of the cloisters.