Dora somehow interrupts classical peace - that's a contradiction in terms (7)
I believe the answer is:
paradox
'contradiction in terms' is the definition.
(paradox is a kind of contradiction in terms)
'dora somehow interrupts classical peace' is the wordplay.
'somehow' is an anagram indicator.
'interrupts' is an insertion indicator.
'classical peace' becomes 'pax' (I've seen this before. I am not sure about the 'classical' bit.).
'dora' with letters rearranged gives 'rado'.
'rado' placed inside 'pax' is 'PARADOX'.
'that's a' acts as a link.
Can you help me to learn more?
(Other definitions for paradox that I've seen before include "[Still without being stll] ?" , "Statement that seems contradictory but expresses truth" , "Statement which seems contradictory but is true" , "Seeming contradiction" , "A seemingly contradictory statement" .)