Learn how to say Decease correctly in English with this tutorial pronunciation video.
Oxford dictionary definition of the word decease:
[in singular] formal or Law
a person’s death:
he held the post until his untimely decease in 1991
[no object] archaic
he deceased at his palace of Croydon
Middle English: from Old French deces, from Latin decessus ‘death’, past participle (used as a noun) of decedere ‘to die’