Given to or marked by deliberate concealment or misrepresentation of the truth
The early difficulties of Elizabeth's reign secured him a deceitful peace on that side for a time.
She felt deceitful pumping Mrs. Marsh for information about Brandon's plans, but it was the perfect opportunity.
But if I'm supposed to avoid the subject, don't act like I'm in the middle of some deceitful act when I try.
Option One used deceitful tactics to trick customers.
It's best to notice patterns in the way that people respond to you to tell if they are truly being deceitful.