One smashing image representing lions and cat without company (10)
I believe the answer is:
iconoclast
'one smashing image' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'representing lions and cat without company' is the wordplay.
'representing' is an anagram indicator (letters must be re-presented in a new way).
'and' is a charade indicator (letters next to each other).
'without' indicates putting letters inside ('without' can be similar in meaning to 'outside').
'company' becomes 'co' (abbreviation).
'lions' put after 'cat' is 'catlions'.
'catlions' anagrammed gives 'inoclast'.
'inoclast' enclosing 'co' is 'ICONOCLAST'.
Can you help me to learn more?
(Other definitions for iconoclast that I've seen before include "heretic" , "A dissident" , "Challenging type" , "Unorthodox thinker" , "Critic of faith" .)