slither - Dictionary definition and meaning for word slither
Slytherine heirs can talk to snakes and hence called so. Snakes slither.
slither itself says slide ker which means move firmly
s + LITHER (lather)... when there is lather on sth. and if you try to catch it it will slip away from ur hands
sly+the(r) sly the person i.e slip him from good position to bad