He starts out to disappear gradually (5)

I believe the answer is:

peter

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'he' is the definition.
(I've seen this before)

I don't understand the remainder of the clue.

(Other definitions for peter that I've seen before include "- Sellers, twentieth century English comedian" , "- Grimes (Britten)" , "Disciple" , "Play high card before low" , "till down under" .)

I've seen this clue in The Globe and Mail.

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