Ethic
late Middle English (denoting ethics or moral philosophy; also used attributively): from Old French éthique, from Latin ethice, from Greek (hē) ēthikē (tekhnē) ‘(the science of) morals’, based on ēthos (see ethos).
wiktionary
From Middle English etik, from Late Latin ēthicus, from Ancient Greek ἠθῐκός(ēthikós).
From Middle English etik, ethik, from Old French ethique, from Late Latin ēthica, from Ancient Greek ἠθική(ēthikḗ), from ἠθικός(ēthikós, “of or for morals, moral, expressing character”), from ἦθος(êthos, “character, moral nature”).
etymonline
ethic (n.)
late 14c., ethik "study of morals," from Old French etique "ethics, moral philosophy" (13c.), from Late Latin ethica, from Greek ēthike philosophia "moral philosophy," fem. of ēthikos "ethical, pertaining to character," from ēthos "moral character," related to ēthos "custom" (see ethos). Meaning "moral principles of a person or group" is attested from 1650s.
