Excited animal that is caught in tangled net (9)
I believe the answer is:
ebullient
'excited' is the definition.
(thesaurus)
'animal that is caught in tangled net' is the wordplay.
'animal' becomes 'bull' (bull is a kind of animal).
'that is' becomes 'ie' (short for Latin 'id est', 'that is').
'caught in' means one lot of letters goes inside another.
'tangled' indicates anagramming the letters.
'bull'+'ie'='bullie'
'net' with letters rearranged gives 'ent'.
'bullie' going inside 'ent' is 'EBULLIENT'.
(Other definitions for ebullient that I've seen before include "Overflowing with enthusiasm" , "Cheerful, full of energy" , "Bubbling over with high spirits, animated" , "Bouncing with enthusiasm" , "bright and breezy?" .)