• WordNet 3.6
    • adj operose characterized by effort to the point of exhaustion; especially physical effort "worked their arduous way up the mining valley","a grueling campaign","hard labor","heavy work","heavy going","spent many laborious hours on the project","set a punishing pace"
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Webster's Revised Unabridged Dictionary
    • a Operose Wrought with labor; requiring labor; hence, tedious; wearisome. "Operose proceeding.""A very operose calculation."
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Century Dictionary and Cyclopedia
    • operose Laborious; attended with labor; tedious.
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Chambers's Twentieth Century Dictionary
    • adj Operose op′ėr-ōz laborious: tedious
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Webster's Revised Unabridged Dictionary
L. operosus, fr. opera, pains, labor, opus, operis, work, labor


In literature:

But what an operose method!
"Essays, Second Series" by Ralph Waldo Emerson
In the execution, it was an operose business on both sides of the water.
"The Works of the Right Honourable Edmund Burke, Vol. IV. (of 12)" by Edmund Burke