Big guy turning tail, bitten by pig (7)
I believe the answer is:
goliath
'big guy' is the definition.
The answer and definition can be both people as well as being singular nouns.
I also know that 'big' relates to this answer.
'turning tail bitten by pig' is the wordplay.
'turning' says the letters should be written in reverse.
'bitten by' means one lot of letters goes inside another (I've seen this in other clues).
'pig' becomes 'hog' (synonyms).
'tail' inserted inside 'hog' is 'htailog'.
'htailog' written backwards gives 'GOLIATH'.
Can you help me to learn more?
(Other definitions for goliath that I've seen before include "David slew him with a slingshot (7)" , "Biblical giant" , "David laid him low with slingshot" , "Giant, David's victim" , "Unusually large person" .)