In a manner that produces profit, income, or advantage; in a way that is profitable or productive.
From 'gainful' plus the adverbial suffix '-ly' (from Old English '-lice'), creating an adverb form that modifies verbs and adjectives.
The phrase 'gainfully employed' became an obsession in bureaucratic language because it neatly divides people into categories the government could track and tax—language and power go hand-in-hand like that.
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