Shrewd sovereign keeping right away (7)
I believe the answer is:
knowing
'shrewd' is the definition.
(I've seen this in another clue)
'sovereign keeping right away' is the wordplay.
'sovereign' becomes 'king' (king is a kind of sovereign).
'keeping' means one lot of letters goes inside another (some letters kept inside).
'right away' becomes 'now' (both can mean immediately).
'king' going around 'now' is 'KNOWING'.
(Other definitions for knowing that I've seen before include "Arch" , "Meaningful" , "Experienced; intelligent" , "Wise" , "Fly" .)