From Longman Dictionary of Contemporary Englishdyed-in-the-woolˌdyed-in-the-ˈwool adjective OPINIONhaving strong beliefs, likes, or opinions that will never change Even dyed-in-the-wool traditionalists were impressed by the changes.
Examples from the Corpus
dyed-in-the-wool• Stahl belongs to that dyed-in-the-wool amateur breed who follow the sun not for money but for fun.• But even a dyed-in-the-wool extravert will sometimes choose to behave more demurely.• He was, however, a hack, a dyed-in-the-wool Fleet Street man.• Allen is a dyed-in-the-wool New Yorker. 