One ruminating about southern Ilium — Shiva? (9)
I believe the answer is:
destroyer
'one ruminating' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'about southern ilium shiva?' is the wordplay.
'about' is an insertion indicator.
'southern' becomes 's' (abbreviation).
'ilium' becomes 'troy' (synonyms).
'shiva?' becomes 'deer' (I am not sure about this - if you are sure you should believe this answer much more).
's'+'troy'='stroy'
'stroy' going into 'deer' is 'DESTROYER'.
Can you help me to learn more?
(Other definitions for destroyer that I've seen before include "Apollyon maybe" , "breaker?" , "likely to break down" , "Large warship" , "One who wrecks" .)