Crossword Genius

To sum up, I go under about hiding answer (2,1,4)

Ross

I believe the answer is:

in a word

'to sum up' is the definition.
(I've seen this before)

'i go under about hiding answer' is the wordplay.
'go under' becomes 'drown' (I've seen this before**).
'about' says the letters should be written backwards.
'hiding' means one lot of letters goes inside another.
'answer' becomes 'a' (abbreviation eg in Q and A).
'drown' written backwards gives 'nword'.
'nword' going around 'a' is 'naword'.
'i'+'naword'='IN A WORD'

(Other definitions for in a word that I've seen before include "Where a number of characters may be found" , "summing up" , "Where letters are usually found" , "To summarize" , "To summarise very briefly" .)

I've seen this clue in The Times.
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