Nominally, he may have a large figure (6)
I believe the answer is:
gerald
'nominally he may have a' is the definition.
The definition suggests a singular noun which matches the answer.
'large figure' is the wordplay.
I cannot really understand how this works, but
an anagram of 'large' is 'geral' which is present in the answer.
A single letter 'd' remains which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for gerald that I've seen before include "- - Ford, ex-US president" , "- Moore, accompanist" .)