Terminal porter possibly finished early after carrying extra baggage (5)
I believe the answer is:
fatal
'terminal' is the definition.
(similar in meaning)
'finished early after carrying extra baggage' is the wordplay.
'finished early' means to remove the last letter (the word finishes earlier than normal).
'after' becomes 'a la' ('a la' - 'in the style of ' or 'after' in French).
'carrying' means one lot of letters go next to another (in a down clue, the bottom letters carry others).
'extra baggage' becomes 'fat' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'ala' with its last letter taken away is 'al'.
'al' put after 'fat' is 'FATAL'.
'porter possibly' is the link.
I am not very happy about this link. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for fatal that I've seen before include "Mortal" , "making one late" , "Bringing ruin" , "Disastrous, maybe lethal" , "Causing or leading up to death" .)