Stop: the respite is cancelled (8)
I believe the answer is:
breakoff
'stop' is the definition.
I know nothing about this answer so I cannot tell whether it can be defined by this definition.
'respite is cancelled' is the wordplay.
'respite' becomes 'break' (synonyms).
'is cancelled' becomes 'off' (similar in meaning).
'break'+'off'='BREAKOFF'
'the' acts as a link.
Can you help me to learn more?
(Other definitions for breakoff that I've seen before include "Put an end to (engagement)" , "Stop short" , "Stop doing (something)" .)