marked by deliberate deceptiveness especially by pretending one set of feelings and acting under the influence of another; "she was a deceitful scheming little thing"- Israel Zangwill; "a double-dealing double agent"; "a double-faced infernal traitor and schemer"- W M Thackeray
Someone who is ambidextrous can use both their right hand and their left hand equally skilfully. able to use either hand equally well left-handed, right-handed right-handed (ambidexter, from ambi- ( AMBI-) + dexter )