For the young, it may offer an enjoyable come-down (5)
I believe the answer is:
slide
'for' is the definition.
Both the answer and definition are singular nouns.
Perhaps you can see an association between them that I can't see?
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for slide that I've seen before include "Trombone part" , "Slip, slither, skid" , "leading to a fall" , "Playground equipment with sloping surface" , "that's put under the microscope" .)