mortgagee (n.)

"to grant (immovable property) as security for money lent or contracted to be paid," late 15c., morgagen, from mortgage (n.). Related: Mortgaged; mortgaging.

word-forming element in legal English (and in imitation of it), representing the Anglo-French -é ending of past participles used as nouns (compare -y (3)). As these sometimes were coupled with agent nouns in -or, the two suffixes came to be used as a pair to denote the initiator and the recipient of an action.

Not to be confused with the French -ée that is a feminine noun ending (as in fiancée), which is from Latin -ata.