Observe article and be furious (6)
I believe the answer is:
seethe
'be furious' is the definition.
(to seethe is to be very angry)
'observe article' is the wordplay.
'observe' becomes 'see' (observe can mean to see something).
'article' becomes 'the' (the definite article in English).
'see'+'the'='SEETHE'
'and' acts as a link.
(Other definitions for seethe that I've seen before include "Of water, bubble or surge as in boiling" , "get very agitated" , "Surge or foam, as if boiling" , "exhibit anger" , "become agitated" .)