laborious

adjective

la·​bo·​ri·​ous lə-ˈbȯr-ē-əs 

1

a

: involving, requiring, or characterized by hard and sustained effort : arduous

Overland travel was not an adventurous communal leap, but a laborious, individual trek.

—Daniel J. Boorstin

Making a telescope mirror is a long and laborious process.

—David Devoss and Eric Sander

b

: characterized by long, detailed elaboration : tedious

Much of the middle of the book is a laborious account of the scouring of the ocean floor that led to the discovery of the Titanic.

—The Economist

2

: devoted to labor : industrious

We have the greatest riches, the greatest fertility, … the most laborious population.

—Joseph Conrad

laboriously adverb

laboriousness noun

Synonyms of laborious

• diligent
• busy
• engaged
• employed

Examples of laborious in a Sentence

a slow and laborious process

the volunteers have been commendably laborious in their cleanup of the beach

Recent Examples on the Web

The policy update, applicable to all reservations booked on or after November 20, is designed to streamline the Airbnb experience after a slew of customer complaints about unclear house rules and laborious demands by property hosts. — Charlotte Reck, CNN Money, 22 Oct. 2026

Heffers supplied libraries and established reading clubs, Blackwell’s undertook the difficult and laborious task of sending books to POWs during the Second World War. — Literary Hub, 20 Oct. 2026

Many of those stripped from the electoral rolls are appealing their removal—an often laborious process—but the possibility of mass disenfranchisement is real. — Pratap Bhanu Mehta, Foreign Affairs, 15 Oct. 2026

Teaching teams how to win, planting seeds of a healthy culture and seeing the fruits of that laborious efforts, is far more important than picking at the top of any draft. — Omar Kelly, Miami Herald, 9 Oct. 2026

Word History

First Known Use

14th century, in the meaning defined at sense 2

Rhymes for laborious

• inglorious
• notorious
• sartorius
• uproarious
• vainglorious
• victorious
• glorious
• meritorious

Kids Definition

laborious

adjective

la·​bo·​ri·​ous lə-ˈbōr-ē-əs 

-ˈbȯr-

1

: devoted to work : industrious

2

: requiring hard effort

laboriously adverb

laboriousness noun