inferior
In all fields and in general use, the opposite of "superior" is "inferior".
The opposite of subordinate (secondary) could be primary, main, predominant, or major.The opposite of subordinate (in authority) could be superior, senior, or ranking.The opposite of the noun subordinate (underling) could be boss, chief, superior, supervisor, or director.
The opposite of the adjective superior is inferior.The opposite of the noun superior may be subordinate, minion, or underling.
Superior is the opposite of inferior.the opposite of inferior is huge,massive,giant
CAUDAL
Superior
superior
Inferior
Superior.
Being superior
There is no opposite condition for highly superior autobiographical memory orhyperthymesia.
For comparing quality, the opposite of "premier" (superior) could be inferior or poor. Where premier assumes the very best, the opposite is worst or poorest.