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

Only Connelly Early has been consistently solid, but even two of his outings so far were short and laborious. —Mac Cerullo, Boston Herald, 19 Apr. 2026

Mine clearing is a laborious and time-consuming process fraught with danger. —Christopher McFadden, Interesting Engineering, 19 Apr. 2026

While individually rolling classic Chicken Cordon Bleu for dinner guests can be laborious, this casserole has all the same flavor (down to the crispy breadcrumbs) with half the effort. —Mary Shannon Wells, Southern Living, 18 Apr. 2026

Robert Campbell built the Mill Creek operation around 1790 specifically to produce lumber and farm crops for sale to the island, replacing laborious hand‑sawing as demand exploded after the British moved Fort Michilimackinac there in 1781. —Andy Morrison, USA Today, 15 Apr. 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