One is seen in exchange of angry words (6)
I believe the answer is:
tirade
'angry words' is the definition.
(I've seen this before)
'one is seen in exchange' is the wordplay.
'one' becomes 'i' (Roman numeral).
'is seen in' is an insertion indicator.
'exchange' becomes 'trade' (trade is a kind of exchange).
'i' inserted into 'trade' is 'TIRADE'.
'of' acts as a link.
(Other definitions for tirade that I've seen before include "A long abusive harangue" , "Blast of criticism" , "Vocal abuse" , "Long speech of angry criticism" , "Loud harangue" .)