Price of a trip? (7)
I believe the answer is:
penalty
'price' is the definition.
(thesaurus)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for penalty that I've seen before include "Punishment eg for foul" , "Perhaps fine" , "Disadvantage imposed" , "Punishment for error (in game)" , "Fine - handicap" .)