economics

From economic (noun) (obsolete) + -s (suffix forming pluralia tantum, and regular plural forms of nouns). Economic is derived from Middle English economike, iconomique (“household management”), and then: * from Middle French iconomique, oeconomique, and Old French iconomike (“(noun) household management; person in charge of household management; (adjective) relating to household management; relating to domestic or family matters; relating to management of a state; reducing costs or expenses, economical”) (modern French économique); and * from their etymon Latin oeconomicus (“(noun) household manager, housekeeper, steward; (adjective) relating to orderly arrangement of written material”) (whence Late Latin economicus (“relating to (management of) a household”)), and economica (“household management”), both from Ancient Greek οἰκονομῐκός (oikonomĭkós, “skilled in household management; frugal, thrifty, economical”) (whence Koine Greek οἰκονομῐκός (oikonomĭkós, “relating to orderly arrangement of written material”)); from οἰκονόμος (oikonómos, “master of a house; household manager, steward; administrator, manager”) + -ῐκός (-ĭkós, suffix meaning ‘of or relating to’ forming adjectives). Οἰκονόμος (Oikonómos) is derived from οἶκος (oîkos, “dwelling place, house; estate”) (ultimately from Proto-Indo-European *weyḱ- (“(verb) to enter in; to settle; (noun) settlement”)) + νόμος (nómos, “law, ordinance”) (from νέμω (némō, “to distribute; to possess”) (ultimately from Proto-Indo-European *nem- (“to distribute; to give; to take”)) + -ος (-os, suffix forming o-grade action nouns from verbs)). By surface analysis, econom(y) + -ics (suffix forming nouns denoting fields of knowledge or practice).

来源：wiktionary