Roll-up to see American pest (5)
I believe the answer is:
roach
'pest' is the definition.
Although both the answer and definition are singular nouns, I cannot see how they can define each other.
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for roach that I've seen before include "Historic SE county" , "Silver and red freshwater fish" , "bedbug in the Waldorf?" , "Freshwatwer fish" , "creepy-crawly" .)