Watch article boil (6)
I believe the answer is:
seethe
'boil' is the definition.
(I know that seethe is a kind of boil)
'watch article' is the wordplay.
'watch' becomes 'see' (see can mean to view or watch).
'article' becomes 'the' (the definite article in English).
'see'+'the'='SEETHE'
(Other definitions for seethe that I've seen before include "Boil; fume with suppressed rage" , "Simmer with anger" , "Be silently angry" , "Bubble gently like boiling water" , "become agitated" .)