Impeach President, ultimately turning decisive (8)
I believe the answer is:
emphatic
'decisive' is the definition.
Both the definition and answer are adjectives. Perhaps there's an association between them I don't understand?
'impeach president ultimately turning' is the wordplay.
'ultimately' indicates one should take the final letters.
'turning' indicates an anagram.
The final letter of 'president' is 't'.
'impeach'+'t'='impeacht'
'impeacht' anagrammed gives 'EMPHATIC'.
Can you help me to learn more?
(Other definitions for emphatic that I've seen before include "Forceful - pronounced" , "For sure" , "Expressing oneself with vigour and conviction" , "Impact he combined with special stress" , "Able to experience another's feelings" .)