Angry about extremely tiresome repeat (7)
I believe the answer is:
iterate
'repeat' is the definition.
(I know that iterate is a more specific form of repeat)
'angry about extremely tiresome' is the wordplay.
'angry' becomes 'irate' (irate can mean angry or annoyed).
'about' indicates putting letters inside.
'extremely' suggests removing the centre (only the extremes of the word are used).
'tiresome' with its middle removed is 'te'.
'irate' going around 'te' is 'ITERATE'.
(Other definitions for iterate that I've seen before include "Recapitulate" , "State repeatedly, say again" , "Utter or perform repeatedly" , "Say again, repeat" , "Repeat, state again" .)