Frightful animal picked up (6)
I believe the answer is:
grisly
'frightful' is the definition.
(I've seen this before)
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for grisly that I've seen before include "Horrific" , "Very unpleasant" , "Causing horror or revulsion" , "Causing horror or disgust" , "Horrible, ghastly" .)