Longman Dictionary of Contemporary English
The Collaborative International Dictionary
Seaman \Sea"man\, n.; pl. Seamen. [AS. s[ae]man.] One whose occupation is to assist in the management of ships at sea; a mariner; a sailor; -- applied both to officers and common mariners, but especially to the latter. Opposed to landman, or landsman.
Able seaman, a sailor who is practically conversant with all the duties of common seamanship.
Ordinary seaman. See Ordinary.
Wiktionary
n. (alternate form of able-bodied seaman English)
WordNet
n. a seaman in the merchant navy; trained in special skills [syn: able-bodied seaman]
Wikipedia
In the British Royal Navy in the middle of the 18th century, the term able seaman (abbreviated AB) referred to a seaman with more than two years' experience at sea and considered "well acquainted with his duty". Seamen with no or more than one year experience at sea are referred to as landmen or ordinary seamen respectively.
An able seaman (AB) is a Naval rating of the deck department of a merchant ship with more than two years' experience at sea and considered "well acquainted with his duty". An AB may work as a watchstander, a day worker, or a combination of these roles. Once a sufficient amount of sea time is acquired, then the AB can apply to take a series of courses/examinations to become certified as an officer.
Usage examples of "able seaman".
Then the men were poor men, accordin' to my idees of what an able seaman should be, or they never would have let their schooner turn turtle with them as she did.
With him died Lieutenant Abraham Cousins, Lieutenant Lisa Dagalow, Machinist Jorge Perez, able seaman Mikhail Arbatov, and six passengers.
Rated in the muster book as an able seaman, and listed as 'the Second' to distinguish him from another seaman of the same name, Smith was also the Kathleen's band.
The able seaman prowled the flowing screens along the bridge console.
Well then, I tell you what, Mr Williams, you find me an able seaman to come along with him and I'll take your boy.
Southwick - old enough, as he said on one occasion when trying to din some mathematics into him, to be his great-grandfather - liked him, so did Alberto Rossi, the Genovese, an able seaman who kept his history in Genoa a secret (most people were sure that he had stabbed a man) but whose casual remarks from time to time gave glimpses of a lurid past.
If some other ship offers him a berth as a petty officer, he's usually a lot better off staying with me as an able seaman.
It was a crazy situation, he reflected, that the success of the First Lord's orders, the intentions of the Board of Admiralty, the desperate need to warn these admirals at sea without a moment's delay that the Fleet at Spithead had mutinied, probably depended at this particular moment not on storms in the Western Ocean, good navigation or Lieutenant Ramage, but on a man called Harris, rated able seaman in the Triton's muster book.
I will give you an able seaman's wages and ask Captain Pullings to enter you as a supernumerary.
But your wish is to get a berth before the mast as an Able Seaman if possible.
She carried no extraordinary cargo - she had meant to fill up her hold with seals' skin down at Mas Afuera - but those Surprises, and there were several of them, who had been on the Nootka run and who had conversed with their prisoners, knew that in sea-otter skins and beaver alone the able seaman's share of the prize would be in the nature of ninety-three pieces of eight.