Q: Regarding your post about “under way,” please note that as the ship Pequod left port it was “getting under weigh.” This was a nautical metaphor that alluded to the process of pulling up anchor to begin a trip.
A: As we wrote in our 2009 post, the original term for a ship moving through the water was “under way,” not “under weigh.” Strictly speaking, a ship “weighs anchor” before getting “under way.”
The Oxford English Dictionary labels “under weigh” a common variant of “under way” that arose “from erroneous association with the phr. ‘to weigh anchor.’ ”
But a term that lexicographers label a “variant” is merely that. It’s not incorrect, just an alternative spelling.
In most dictionaries, the “variant” label means the spelling is acceptable in standard English, unless a more restrictive label, like “dialect” or “slang” or “offensive,” is also appended.
Both of these nautical expressions date from the 18th century. Oxford’s earliest example of “under way” in English writing is from 1743, and the earliest for “under weigh” is from 1777.
The dictionary describes the earlier “under way” as a nautical term from the Dutch onderweg or onderwegan.
In Dutch, a language from which English adapted many nautical terms, onder means “under, in the course of, etc.,” and weg means “way.” The phrase, the OED says, is “often spelt under weigh.”
What do standard American dictionaries say about “under weigh”?
Merriam-Webster’s Collegiate Dictionary (11th ed.) says “under weigh” was derived “by folk etymology” from “under way.”
The American Heritage Dictionary of the English Language (5th ed.) says that the “weigh” here is a variant of “way” that was “influenced by weigh, as in weigh anchor.”
Webster’s New World College Dictionary (4th ed.) says much the same: in the phrase “under weigh,” the dictionary notes, the use of “weigh” for “way” is a spelling “modified by the notion of ‘weighing anchor.’ ”
The online Random House Kernerman Webster’s College Dictionary makes no mention at all of “under weigh.” It has only “under way,” and uses the example “The ship is under way.” Elsewhere, Random House defines “weigh anchor” as “to heave up a ship’s anchor in preparation for getting under way.”
In short, most dictionaries accept “under weigh” as a variant. And in our opinion it’s so firmly established in nautical usage that it’s no longer remarkable, though “under way” is preferable on etymological grounds.
As for your comment about Herman Melville’s use of “under weigh” in Moby-Dick, he wasn’t the only literary figure to choose the variant.
As Michael Quinion notes on his website World Wide Words, the usage “has the ghostly support of generations of writers.”
In addition to Melville, Quinion cites William Makepeace Thackeray, Captain Frederick Marryat, Washington Irving, Thomas Carlyle, Lord Byron, Charles Dickens, and C. S. Forester.
The mistaken spelling was perhaps inevitable. As Quinion says, “Some over-clever individuals connected with the sea almost immediately linked it erroneously with the phrase to weigh anchor. “
Here are the two earliest examples for each term, courtesy of the OED:
1743: “To prevent which, we do agree, that when Under-way they shall not separate.” (From A Voyage to the South-Seas in the Years 1740-1, by the shipmates John Bulkeley and John Cummins.)
1751: “We drew up the two boats, and set all hands at work to put the ship under way.” (From Robert Paltock’s novel The Life and Adventures of Peter Wilkins.)
1777: “I can assure you on the authority of Mr. Sullivan, that he saw him underweigh in the Bessborough and for the East Indies several Weeks ago.” (From a letter written by E. Draper, and later published in the journal Notes and Queries in 1944.)
1785: “This perverse wind has at last … come about to the east, so that we are all in high spirits getting under weigh.” (From a piece by Richard Cumberland, published in the Observer, London.)
As you can see, it didn’t take the variant long to catch on.
from Grammarphobia http://www.grammarphobia.com/blog/2015/12/under-weigh.html