Poor language principal has avoided, well-bred chap (8)
I believe the answer is:
indigent
'poor' is the definition.
('indigent' can be similar in meaning to 'poor')
'language principal has avoided well-bred chap' is the wordplay.
I cannot quite understand how this works, but
'chap' could be 'gent' (I've seen this in other clues) and 'gent' is found within the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for indigent that I've seen before include "Poor and needy" , "Poor enough to need help from others" , "Impoverished, destitute" , "Impoverished -- ending it (anag)" , "Needy, poverty-stricken" .)