Word of greeting witness's spoken? (6)

I believe the answer is:

wotcha

'word of greeting' is the definition.
(wotcha is an informal greeting)

'witness's spoken?' is the wordplay.
'witness' becomes 'watcher' (someone who watches).
'spoken?' shows a homophone (sound like).
'watcher' sounds like 'WOTCHA'.

(Other definitions for wotcha that I've seen before include "Hello!" , "Opener" .)

I've seen this clue in The Times.

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