See decease in American Heritage Dictionary 4
intransitive verb de·ceased, de·ceas·ing, de·ceas·es
Origin:
Origin: Middle English decesen
Origin: , from deces, death
Origin: , from Old French
Origin: , from Latin dēcessus, departure, death
Origin: , from
Origin: past participle of dēcēdere, to depart, die
Origin: : dē-, de-
Origin: + cēdere, to go; see ked- in Indo-European roots
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