Ship it requires nerve for one to travel on (7)
I believe the answer is:
galleon
'ship' is the definition.
(I've seen this before)
'for one to travel on' is the wordplay.
'for' becomes 'gall' (I can't justify this - if you can you should give a lot more credence to this answer).
'to travel' indicates an anagram (I've seen 'travelled' mean this).
'on' means one lot of letters goes inside another (as in clothing \'on\' a person).
'one' is an anagram of 'eon'.
'gall' inserted inside 'eon' is 'GALLEON'.
'it requires nerve' acts as a link.
This may not be right. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for galleon that I've seen before include "Spanish treasure ship" , "Old Spanish ship" , "One might sink" , "Historical warship with three or more masts" , "All gone (anag.)" .)