first mate

American

noun

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

first mate British

noun

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

This is akin to attributing a ship’s safe passage through rough seas to the first mate, not the captain.

From Los Angeles Times • Oct. 11, 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

The first mate, she reads, struggled furiously with other monsters which were climbing up the sides of the Nautilus.

From "All the Light We Cannot See" by Anthony Doerr

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