Oman

Oman, a territory of Arabia, lying along the shores of the Persian Gulf and the Arabian Sea, round the south-eastern nob of the peninsula; has some stretches of very fertile country where there happens to be water for irrigation, but the coast is very hot and not healthy. The region is subject to the Sultan of Muscat, who is in turn a pensioner of the Anglo-Indian Government.

Definition taken from The Nuttall Encyclopædia, edited by the Reverend James Wood (1907)

Omaha * Omar
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Olmütz
Olympia
Olympiad
Olympias
Olympic Games
Olympus
Olney
Om
Omagh
Omaha
Oman
Omar
Omar Khayyám
Omar Pasha
O'Meara, Barry Edward
Ommiades
Omnipresence
Omphalë
Omsk
Onega, Lake
Onomatopœia