screff
Screff is a derogatory term for a contemptible person. There is no set of necessary and sufficient conditions which if fulfilled make a person a screff. The only necessary condition is that the person lacks self-awareness: they are unaware that their actions and behaviour make them a screff. Beyond this condition the only way to explain the meaning of screff is to enumerate examples of people who are screffs. In this way certain ‘family resemblences’ among screffs will become apparent (screff is an example of a Wittgensteinian family resemblance concept). Examples of notable screffs are:

Simon Cowell
Boris Johnson

Sir Alan Sugar
Jordan (a.k.a. Katie Price)
Cheryl Cole
Jamie Oliver
Jamiroquai
Jeremy Clarkson
Richard Hammond

The adjective Screffy can also be used to describe non-persons such as TV shows, films, music, clothes and activities that are associated with screffs.
'Simon Cowell, what a screff!'
'Humvees are proper screffy'