noun
( -es )
Etymology: Middle English sleghness, slinesse, from slegh, sli sly + -ness, -nesse -ness
: the quality or state of being sly: as
a. : shrewdness , craftiness
a very weak position of which the bishop with praiseworthy slyness took full advantage — T.S.Eliot
b. : secretiveness
led him to escape … the next morning with admirable slyness — Jane Austen