Loyal father getting group to twitch (9)
I believe the answer is:
patriotic
'loyal' is the definition.
(I know that loyal can be written as patriotic)
'father getting group to twitch' is the wordplay.
'father' becomes 'pa' (pa can mean dad or father).
'getting group' becomes 'trio' (I am not sure about this - if you are sure you should believe this answer much more).
'to twitch' becomes 'tic' (tic is a kind of twitch).
'pa'+'trio'+'tic'='PATRIOTIC'
Can you help me to learn more?
(Other definitions for patriotic that I've seen before include "flag-waving?" , "Loyal" , "Supporting the state" , "Devoted to one's country" , "Having love for one's country" .)