Visual science test follows work on book (9)

I believe the answer is:

optometry

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

'test follows work on book' is the wordplay.
'test' becomes 'try' (synonyms).
'follows' means one lot of letters go next to another.
'work on' becomes 'op' (common abbreviation for 'opus'. I am not sure about the 'on' bit.).
'book' becomes 'tome' (a tome is a book).
'op'+'tome'='optome'
'try' after 'optome' is 'OPTOMETRY'.

Can you help me to learn more?

(Other definitions for optometry that I've seen before include "Science of vision and eye-care" , "Visual science" , "can help you see things more clearly" , "Motor type (anag.)" , "examining pupils, etc" .)

I've seen this clue in The Telegraph.

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