internal

The story

1. New Latin · derived frominternālis“of or pertaining to the inner part”
2. Middle English · inherited frominternall, internalle
3. English todayinternal

From Middle English internall, internalle, borrowing from New Latin internālis (“of or pertaining to the inner part”), from internus (“inward, internal”) + -ālis (“-al”, adjectival suffix). By surface analysis, intern + -al.