Live troll oddly ignored American convict, current leader who partied with young girls (10)
I believe the answer is:
berlusconi
'leader who partied with young girls' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.
'live troll oddly ignored american convict current' is the wordplay.
'live' becomes 'be' (synonyms).
'oddly ignored' indicates alternate letters (letters in odd-numbered positions are removed).
'american' becomes 'US' (United States).
'convict' becomes 'con' (abbreviation e.g. 'ex-con').
'current' becomes 'I' (physics symbol).
The alternating letters of 'troll' are 'rl'.
'be'+'rl'+'us'+'con'+'i'='BERLUSCONI'
Can you help me to learn more?