from The American Heritage® Dictionary of the English Language, 4th Edition
- adj. Marked by or requiring long, hard work: spent many laborious hours on the project.
- adj. Hard-working; industrious.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. Requiring much physical effort; toilsome.
- adj. Mentally difficult; painstaking
- adj. Industrious.
from the GNU version of the Collaborative International Dictionary of English
- adj. Requiring labor, perseverance, or sacrifices; toilsome; tiresome.
- adj. Devoted to labor; diligent; industrious.
from The Century Dictionary and Cyclopedia
- Requiring much labor, exertion, or perseverance; toilsome; not easy: as, laborious duties; a laborious undertaking.
- Using exertion; practising labor; diligent in work or service; assiduous: as, a laborious husbandman or mechanic; a laborious minister or pastor.
- Characterized by labor or effort; marked by or manifesting labor.
- Synonyms Difficult arduous, wearisome, fatiguing, onerous.
- Industrious, painstaking, active, hard-working.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- adj. characterized by effort to the point of exhaustion; especially physical effort
Middle English, from Old French laborieux, from Latin labōriōsus, from labor, labor.(American Heritage® Dictionary of the English Language, Fourth Edition)