Oddly edgy on ship’s departure (6)
I believe the answer is:
egress
'departure' is the definition.
(thesaurus)
'oddly edgy on ship's' is the wordplay.
'oddly' indicates alternate letters.
'on' becomes 're' ('on' can be mean 'with reference to'**).
'ship' becomes 'ss'.
The alternating letters of 'edgy' are 'eg'.
'eg'+'re'+'ss'='EGRESS'
(Other definitions for egress that I've seen before include "The act of going out" , "Way out of serges" , "At the right moment" , "Way out, departure" , "Way out or means of exit" .)