c.1200, "gentle, courteous, kind," from O.N. mjukr "soft, pliant, gentle," from P.Gmc. *meukaz (cf. Goth. muka-modei "humility," Du. muik "soft"), of uncertain origin. Use to translate L. mansuetus from Vulgate (see mansuetude). Sense of "submissive" is from mid-14c.