c.1300, las "a blow, a stroke," later "flexible part of a whip" (late 14c.), possibly imitative. The verb might be the source of the noun.
"to strike with a whip," c.1300, "to deal a blow;" later "to whip" (late 14c.); see lash (n.). Lash out "to strike out violently" is from 1560s. Related: Lashed; lashing.
"bind," 1620s, originally nautical, from Middle French lachier, from Old French lacier "to lace" (see lace (v.)). Related: Lashed; lashing.