From The Collaborative International Dictionary of English v.0.48 :
Avowee \A*vow`ee"\, n. [F. avou['e]. Cf. Advowee, Advocate,
n.]
The person who has a right to present to a benefice; the
patron; an advowee. See Advowson.
[1913 Webster]
From Bouvier's Law Dictionary, Revised 6th Ed (1856) :
AVOWEE, eccl. law. An advocate of a church benefice.