high seas

from The American Heritage® Dictionary of the English Language, 4th Edition

• n.pl. The open waters of an ocean or a sea beyond the limits of the territorial jurisdiction of a country: piracy on the high seas.

from Wiktionary, Creative Commons Attribution/Share-Alike License

• n. Parts of the ocean surface that are far from shore.
• n. International waters; parts of the ocean that are not considered to belong to any specific country.

from the GNU version of the Collaborative International Dictionary of English

• adj. the open sea; the part of the ocean not in the territorial waters of any particular sovereignty, usually distant three miles or more from the coast line.