Tempers involving Knight turn oddly for checks (8)
I believe the answer is:
controls
'for checks' is the definition.
('control' can be a synonym of 'check')
'tempers involving knight turn oddly' is the wordplay.
'tempers' becomes 'cools' (I can't justify this - if you can you should believe this answer much more).
'involving' indicates putting letters inside.
'knight' becomes 'N' (chess abbreviation).
'oddly' indicates alternate letters (letters in the odd-numbered positions are used).
The alternate letters of 'turn' are 'tr'.
'n'+'tr'='ntr'
'cools' going around 'ntr' is 'CONTROLS'.
Can you help me to learn more?
(Other definitions for controls that I've seen before include "Regulates" , "Directs, governs" , "Directs or operates" , "Manages the regulatory mechanisms" , "Runs" .)