Which gulf forms the northeastern arm of the Arabian Sea between Iran and Oman?

The Gulf of Oman forms the northeastern arm of the Arabian Sea between Iran and Oman.

This gulf is a deep-water inlet of the Indian Ocean, linking the Arabian Sea westward to the Strait of Hormuz. That strait then opens into the Persian Gulf, making the Gulf of Oman part of one of the world's most important maritime routes.

Its northern shores include Iran and a small portion of Pakistan, while Oman occupies much of the southern coast. The United Arab Emirates also borders its western end near the Strait of Hormuz. Major ports include Chabahar in Iran, Port Sultan Qaboos in Oman, and Fujairah in the UAE.

A common mix-up is confusing it with the Persian Gulf. The Gulf of Oman lies east of the Strait of Hormuz; the Persian Gulf lies west of it. The waterway is also known historically as the Sea of Oman, Gulf of Makran, or Sea of Makran.