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first mate

American  

noun

  1. the officer of a merchant vessel next in command beneath the captain.

first mate British  

noun

  1. Also called: first officer.  an officer second in command to the captain of a merchant ship

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

French authorities boarded the vessel in September, briefly detaining its captain and first mate.

From Barron's • Feb. 23, 2026

She lists the many infractions the first mate committed and defies any among them to countermand her husband’s orders.

From The Wall Street Journal • Dec. 8, 2025

At dusk on the second day, about 75 Rongelapese crowded the decks and cabins of the ship, many of them huddling under a tarp the ship’s first mate, Martini Gotjé, had strung up.

From Slate • Jul. 22, 2025

"We saw a red flare, so my first mate and I went to the position, and we found this life raft drifting," he told Reuters.

From BBC • Aug. 19, 2024

Nathaniel Eaton, first mate, but his mother called him Nat.

From "The Witch of Blackbird Pond" by Elizabeth George Speare

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.