lieutenant

noun

lieu·​ten·​ant lü-ˈte-nənt 

British le(f)-

1

a

: an official empowered to act for a higher official

The king's lieutenant handled the problem.

b

: an aide or representative of another in the performance of duty : assistant

Her best lieutenant was working on the proposal.

2

a(1)

: first lieutenant

(2)

: second lieutenant

b

: a commissioned officer in the navy or coast guard ranking above a lieutenant junior grade and below a lieutenant commander

c

: a fire or police department officer ranking below a captain

Synonyms of lieutenant

• assistant
• adjutant
• aide
• deputy
• apprentice
• aid

Examples of lieutenant in a Sentence

He was promoted to the rank of lieutenant.

She has her best lieutenants working on a proposal.

one of the mobster's most loyal lieutenants

Recent Examples on the Web

The department has transferred a captain, a lieutenant, and six Brooklyn Narcotics detectives who made up the team that ran the botched buy-and-bust operation in the aftermath of the video. —Rocco Parascandola, New York Daily News, 19 Apr. 2026

My longtime chief lieutenant test driver, Roger Adams, joined me for part of the drive and quickly came away impressed. —Sponsored Content, Denver Post, 17 Apr. 2026

Upon joining the department, he was assigned to Engine 56, and rose through the ranks to become a fire lieutenant in 1998. —Gayla Cawley, Boston Herald, 16 Apr. 2026

The former Yolo County sheriff’s lieutenant at the center of the ferocious Esparto fireworks warehouse explosion that killed seven workers last July pleaded not guilty in Woodland to murder and explosives charges in the deadly blast. —Sacbee.com, 16 Apr. 2026

Word History

Etymology

Middle English, from Anglo-French lieu tenant, from liu + tenant holding, from tenir to hold, from Latin tenēre — more at thin

First Known Use

14th century, in the meaning defined at sense 1a

Phrases Containing lieutenant

• first lieutenant
• flight lieutenant
• lieutenant colonel
• lieutenant commander
• lieutenant general
• lieutenant governor
• lieutenant junior grade
• second lieutenant

Rhymes for lieutenant

• cotenant
• subtenant
• pennant
• tenant

Kids Definition

lieutenant

noun

lieu·​ten·​ant lü-ˈten-ənt 

1

: an official who acts for a higher official

2

a

: first lieutenant

b

: second lieutenant

c

: a naval commissioned officer with a rank just below that of lieutenant commander

d

: a fire or police department officer ranking below a captain

Etymology

Middle English lieutenant "lieutenant," from early French lieutenant (same meaning), literally, "one holding the place for another," from lieu "place, position" and tenant "holding"

Word Origin

The phrase in lieu of means the same thing as in place of or instead of. The word lieu came into English from early French, in which it meant "place, position, function." Another English word that came from early French is tenant. In early French, this word was an adjective meaning "holding." Joined together, these two words gave the early French word lieutenant. It originally meant "a person holding another person's place" or "a person acting in place of another." In English, lieutenant is best known as a military title, but the word is still sometimes used in its original meaning to refer to a person who acts in lieu of someone else.