Sublime Porte

Meanings

1. The monumental portal at the Ottoman palace where the supreme tribunals were held; became the surname of the first palace in Bursa, transferred to the even grander Topkapı palace after the capital's transfer to Istanbul (the former Byzantine imperial capital Constantinople)
2. The Ottoman sultanic court, hence the imperial government, notably the vizierial divan and the entire empire, or a personage with a similar standing.

Etymology

From French Sublime Porte (“high gate/portal”).