Horrify a very quiet little chap (5)

I believe the answer is:

appal

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'horrify' is the definition.
('appal' can be a synonym of 'horrify')

'a very quiet little chap' is the wordplay.
'very quiet' becomes 'pp'.
'little' means to remove the last letter (the word is not quite complete).
'chap' becomes 'pal' (I can't justify this - if you can you should believe this answer much more).
'pp' with its final letter taken away is 'p'.
'a'+'p'+'pal'='APPAL'

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(Other definitions for appal that I've seen before include "Outrage" , "Greatly dismay" , "exhibiting dismay" , "Scandalise" , "Greatly horrify" .)

I've seen this clue in the Evening Standard.

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