An Etymological Dictionary of the German Language/Annotated/geschlacht
geschlacht, adjective, ‘of good quality, soft, tender, shapely,’ from Middle High German geslaht, Old High German gislaht, ‘well brought up, noble, well behaved’; ungeschlacht, ‘uncouth, unwieldy, boorish,’ even in Middle High German ungeslaht, Old High German ungislaht, ‘ignoble, base.’ Allied to Modern High German Geschlecht, neuter, ‘species, race, extraction, family,’ from Middle High German geslehte, neuter, ‘race, tribe, family, quality,’ Old High German gislahti; compare Old High German slahta, feminine, ‘race, family,’ Middle High German slahta, ‘manner, relation’; akin also to Schlag (e.g. Menschenschlag, ‘race of men’), not found in Old High German and Middle High German. It is difficult to determine the relation of these cognates to schlagen; even in Old High German slahan itself means ‘to take after, resemble’ (e.g. nâh dên fordôrôn slahan, ‘to resemble one's ancestors’), for which in late Middle High German nâch-slahen occurs, Modern High German nachschlagen. Probably the strong verb in Old Teutonic once had the meaning ‘to beget,’ which cannot now be authenticated; of this verb Old High German gislaht, ‘of good quality,’ would be an old participle in to (see falt, traut, laut), with a development of meaning similar to that of König. Compare French gentil, equivalent to Latin gentilis.