I am beat around four, being hasty (9)
I believe the answer is:
impulsive
'hasty' is the definition.
(thesaurus)
'i am beat around four' is the wordplay.
'i am' becomes 'I'm' (contraction).
'beat' becomes 'pulse' (synonyms).
'around' means one lot of letters goes inside another.
'four' becomes 'IV' (Roman numerals).
'pulse' placed around 'iv' is 'pulsive'.
'im'+'pulsive'='IMPULSIVE'
'being' acts as a link.
(Other definitions for impulsive that I've seen before include "Hot-headed" , "Done without forethought" , "responding promptly" , "Acting without forethought" , "Rash" .)