Wiktionary
high sea
n. The sea when it is very rough due to strong winds and storms, such that the sea encroaches much further inland than is normal, often causing damage.
WordNet
high sea
n. the open seas of the world outside the territorial waters of any nation [syn: international waters] [ant: territorial waters, territorial waters]
Usage examples of "high sea".
Out here, away from the constraints of society, the high seas will be our home.