Commentator's spotted a spinner (6)
I believe the answer is:
spider
'spinner' is the definition.
(a spider spins webs)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for spider that I've seen before include "A crawler" , "Bathtub intruder - snooker rest" , "Eight-legged webmaster?" , "Insect-eater" , "Prised out the 8-legged creature" .)