Have me prattle inordinately, getting the last word in — too excitable? (13)
I believe the answer is:
temperamental
'too excitable?' is the definition.
(temperamental can mean over-excited)
'have me prattle inordinately getting the last word' is the wordplay.
I cannot really understand how this works, but
'me' is found in the answer.
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is found in the answer.
'last' could be 't' (I've seen this in other clues) and 't' is present in the answer.
This may be the basis of the clue (or it may be nonsense).
'in' acts as a link.
(Other definitions for temperamental that I've seen before include "Touchy, moody" , "Erratic" , "Having a volatile disposition" , "Capricious" , "Difficult" .)