To be over dressed 'as a ponce' especially if one is ordinarily rather
conservative in dress. Applies mainly to men. Not a
compliment but an observation, sometimes with negative connotations.
eg a man dressed in a suit and tie for a date or interview and wearing sftershave, when he normally dresses casually and is unshaven, is an example of someone who is 'poncified'.
See the film 'Alfie' starring
Michael Caine, where the word is used.