Dexterous is from Latin dexter ('right-handed, skillful') + English -ous, from Proto-Indo-European *deḱs- ('right side'). The ancestry passes through Latin dexter and Proto-Indo-European *deḱs-. In present use as an adjective, it means "skillful with the hands or mentally adroit", keeping the historical formation close to the word's ordinary semantic work. Related words include dexterity, dextrous, ambidextrous, and dexter; derived forms include dexterously and dexterousness. Its contrast set includes clumsy, awkward, inept, and maladroit, which clarifies the semantic boundary of the modern word.