Helpful hint involving end of pier ride (4)
I believe the answer is:
trip
'ride' is the definition.
(thesaurus)
'helpful hint involving end of pier' is the wordplay.
'helpful hint' becomes 'tip'.
'involving' is an insertion indicator.
'end of' suggests the final letters.
The last letter of 'pier' is 'r'.
'tip' placed around 'r' is 'TRIP'.
(Other definitions for trip that I've seen before include "Journey; make a mistake" , "blunder" , "Run lightly" , "Ride" , "Journey - miss one's footing" .)