From BiblePortal Wikipedia

King James Dictionary [1]

Dece'Ased, pp. or a. Departed from life. This is used as a passive participle. He is deceased, for he has deceased he was deceased, for he had deceased. This use of the participle of an intransitive verb is not infrequent, but the word omitted is really has. He has deceased. It is properly an adjective, like dead.

Webster's Dictionary [2]

(1): ( imp. & p. p.) of Decease

(2): ( a.) Passed away; dead; gone.