Fake painting, if one spies top of laptop (10)
I believe the answer is:
artificial
'fake' is the definition.
(similar in meaning)
'painting if one spies top of laptop' is the wordplay.
'painting' becomes 'art' (painting is an art).
'one' becomes 'i' (Roman numeral).
'spies' becomes 'CIA' (Central Intelligence Agency).
'top of' suggests taking the first letters.
The first letter of 'laptop' is 'l'.
'art'+'if'+'i'+'cia'+'l'='ARTIFICIAL'
(Other definitions for artificial that I've seen before include "Kiss of life" , "Contrived, false" , "Bogus" , "Assumed" .)