Pronunciation: (lu-bôr'ē-us, -bōr'-), [key]
1. requiring much work, exertion, or perseverance: a laborious undertaking.
2. characterized by or requiring extreme care and much attention to detail: laborious research.
3. characterized by or exhibiting excessive effort, dullness, and lack of spontaneity; labored: a strained, laborious plot.
4. given to or diligent in work: a careful, laborious craftsman.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.