From an unused root meaning to alienate; a mongrel, i.e. Born of a Jewish father and a heathen mother -- bastard.
מַמְזֵר noun masculine bastard, specifically child of incest (Late Hebrew id. (see Levy), מַמְזֵרוּת incest; Aramaic (loan-word) מַמְזֵרָא bastard): —
1 literally bastard, Deuteronomy 23:3 (see Dr).
2 perhaps figurative collective, of mixed population Zechariah 9:6 ᵐ5 ἀλλογενεῖς (compare also GeiUrschrift 52f.)
II. מזר (√ of following, si vera lectio; possibly = spread out; Aramaic stretch oneself, compare Arabic aequaliter distendit utrem).