This word originates from the Latin “opus,” meaning “work.” You might recognize that word from artistic or musical pursuits, as a “magnum opus” is an artist’s most important work. In the 16th century, “operose” as an adjective was mostly used to describe people, in the sense of “industrious.” It took about a century for the word’s meaning to shift toward describing inanimate things, such as difficult tasks. For a musician to create their magnum opus, it could take years of operose work.