A fisherman or fishing boat that uses longlines(noun)
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Use "longliner" in a sentence
"At the same time, the numbers of large cod in deep water near the coast of Newfoundland are thought to have declined quickly as the longliner fleet switched to synthetic gillnets."
"As a commercial fisherman on a factory longliner in the Bering Sea, the Gulf of Alaska and near the Aleutian Islands, I have had plenty of opportunities to observe killer whales up close and personal."
"Bosun Kalifi Ferretti-Gallon untangling line confiscated from the Uruguayan longliner La Paloma."