Dear Geist,
Where did the term
come from? In the three dictionaries I checked, it's defined as a significant and/or unexpected change, some important transformation. How does the sea get into it?

Dear Oksana,
The term comes from Shakespeare's play
to other uses—any invocation of the sea reminds us of its beauty and mystery and power superior to ours. And language is a living, changing thing. But it's okay to be sad that we've lost the original, which is in a category of its own.
—The Editors