Eccentric in hot pants got to show great determination (4,2,7)
I believe the answer is:
stop at nothing
'to show great determination' is the definition.
I can't judge whether this defines the answer.
'eccentric in hot pants got' is the wordplay.
'eccentric' indicates anagramming the letters.
'in'+'hot'+'pants'+'got'='inhotpantsgot'
'inhotpantsgot' is an anagram of 'STOP AT NOTHING'.
Can you help me to learn more?
(Other definitions for stop at nothing that I've seen before include "3 [COUNTDOWN CONUMDRUM] will" , "as announcers of rocket launches do?" , "Be totally ruthless" , "Ignore all scruples" , "Act ruthlessly" .)