early 13c., from Old English (ge)slegen, past participle of slean "to smite, strike, beat" (see slay (v.)). The noun meaning "those who have been slain" is attested from mid-14c.
a picture of St. George and the slain dragon
slacker
slack-jawed
slackly
slackness
slag
slain
slake
slalom
slam
slammer
slander
