Tory grandee's hot with fever (5)
I believe the answer is:
hague
'tory grandee's' is the definition.
(Tory peer William Hague)
'hot with fever' is the wordplay.
'hot' becomes 'h' (abbreviation eg on taps).
'with' means one lot of letters go next to another.
'fever' becomes 'ague' (illness causing fever).
'h'+'ague'='HAGUE'
(Other definitions for hague that I've seen before include "The city of the International Court of Justice" , "The ..... is the Netherlands seat of government" , "William -, former Conservative leader" , "politician" .)