-vish, -vēsh adjective
Etymology: Middle English knavyssh, from knave + -yssh, -ish -ish
: having the characteristics of or appropriate to a knave:
a. obsolete : mischievous , roguish
a knavish lad, thus to make poor females mad — Shakespeare
b. : dishonest , fraudulent
knavish booksellers put forth volumes of trash — T.B.Macaulay