From The Collaborative International Dictionary of English v.0.48:
Slay \Slay\, v. t. [imp. Slew; p. p. Slain; p. pr. & vb. n. Slaying.] [OE. slan, sl?n, sleen, slee, AS. sle['a]n to strike, beat, slay; akin to OFries. sl[=a], D. slaan, OS. & OHG. slahan, G. schlagen, Icel. sl[=a], Dan. slaae, Sw. sl?, Goth. slahan; perhaps akin to L. lacerare to tear to pieces, Gr. ????, E. lacerate. Cf. Slaughter, Sledge a hammer, Sley.] To put to death with a weapon, or by violence; hence, to kill; to put an end to; to destroy. [1913 Webster]
With this sword then will I slay you both. --Chaucer. [1913 Webster]
I will slay the last of them with the sword. --Amos ix. 1. [1913 Webster]
I'll slay more gazers than the basilisk. --Shak. [1913 Webster]
Syn: To kill; murder; slaughter; butcher. [1913 Webster]