Light in villa? Seriously? (5)
I believe the answer is:
laser
'light' is the definition.
(lasers are a type of light)
'in villa? seriously?' is the wordplay.
'in' indicates a hidden word.
'LASER' is hidden in the letters of 'villa seriously'.
(Other definitions for laser that I've seen before include "Source of light; type of printer" , "Surgical device" , "Device producing an intense light beam - kind of sailing dinghy" , "Device producing a narrow, intense beam of light" , "scientific device" .)