Shortened game in these days (8)
I believe the answer is:
abridged
'shortened' is the definition.
('abridge' can be a synonym of 'shorten')
'game in these days' is the wordplay.
'game' becomes 'bridge' (card game).
'in' means one lot of letters goes inside another.
'these days' becomes 'AD' (as in Anno Domini, after Christ).
'bridge' inserted within 'ad' is 'ABRIDGED'.
(Other definitions for abridged that I've seen before include "Epitomised" , "Shorter" , "Abbreviated, contracted" , "Cut short - big adder (anag)" , "Shortened as book may be" .)