Tacky (5)
I believe the answer is:
cheap
'tacky' is the definition.
(I know that tacky can be written as cheap)
This is the entire clue.
(Other definitions for cheap that I've seen before include "Inexpensive or tasteless" , "Contemptible" , "Budget -cheesy" , "Low in price or tastelessly showy" , "Not expensive - trashy" .)