LABORIOUS Meaning of LABORIOUS in English [la.bo.ri.ous] adj (14c) 1: devoted to labor: industrious 2: involving or characterized by hard or toilsome effort: labored -- la.bo.ri.ous.ly adv -- la.bo.ri.ous.ness n Merriam-Webster English vocab. Английский словарь Merriam Webster. 2012