Small coin (4)
'small coin' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for penny that I've seen before include "Small unit of currency" , "Lancaster" , "Coin spent by the desperate?" , "Denarius" , "one might drop" .)
'small coin' is the definition.
(eg a US cent)
This is the entire clue.
(Other definitions for cent that I've seen before include "One-hundredth of a currency" , "Little bit of money" , "One hundreth of a dollar" , "One hundredth of a dollar" , "Small amount of money" .)