E.g. Jerry covering Tom up with horse hair (9)
I believe the answer is:
moustache
'horse hair' is the definition.
'moustache' can be an answer for 'hair' (moustache is a kind of hair). I am not sure about the 'horse' bit.
'e g jerry covering tom up' is the wordplay.
'e g jerry' becomes 'mouse' (Jerry from Tom and Jerry is a mouse).
'covering' indicates putting letters inside.
'tom up' becomes 'tach' (I can't explain this - if you can you should believe this answer much more).
'mouse' enclosing 'tach' is 'MOUSTACHE'.
'with' is the link.
Can you help me to learn more?
(Other definitions for moustache that I've seen before include "Food trap" , "Facial feature" , "Facial adornment" , "legacy of Zapata?" , "Facial hair on a man" .)