Starting to bellow a hot word of contempt (3)
I believe the answer is:
bah
'word of contempt' is the definition.
(I've seen this in another clue)
'starting to bellow a hot' is the wordplay.
'starting to' suggests taking the first letters.
'hot' becomes 'h' (abbreviation eg on taps).
The first letter of 'bellow' is 'b'.
'b'+'a'+'h'='BAH'
(Other definitions for bah that I've seen before include "Exclamation of disgust or annoyance" , "Comic expression of contempt" , "Exclamation of contempt or disgust - Scrooge used to say it" , "''...! Humbug!'' (Scrooge)" , "Appalling!" .)