Way to spur fish (8)
I believe the answer is:
sturgeon
'fish' is the definition.
(sturgeon is a kind of fish)
'way to spur' is the wordplay.
'way' becomes 'st' (abbreviation for street).
'to spur' becomes 'urgeon' (as in spurring or urging someone on).
'st'+'urgeon'='STURGEON'
(Other definitions for sturgeon that I've seen before include "The fish for caviars" , "Fish from which caviar is obtained" , "Fish producing caviare" , "Fish producing caviar" , "Caviar-producing fish" .)