Tireless Tsipras initially dividing Greece in broadcast (9)
I believe the answer is:
energetic
'tireless' is the definition.
('energetic' can be similar in meaning to 'tireless')
'tsipras initially dividing greece in broadcast' is the wordplay.
'initially' suggests taking the first letters.
'dividing' indicates putting letters inside.
'broadcast' is an anagram indicator.
The first letter of 'tsipras' is 't'.
'greece'+'in'='greecein'
'greecein' with letters rearranged gives 'energeic'.
't' put into 'energeic' is 'ENERGETIC'.
(Other definitions for energetic that I've seen before include "It's vital" , "Showing great activity" , "Vigorous and dynamic" , "Forceful, vigorous" , "Forceful and with great vitality" .)