Is it a rib-tickler? (5,4)
I believe the answer is:
funny bone
'it a rib-tickler?' is the definition.
The definition suggests a singular noun which matches the answer.
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for funny bone that I've seen before include "part of arm" , "Part of elbow with sensitive nerve - hilarious" , "exposed nerve" , "found up one's sleeve" , "Humerus" .)