The definition of two-faced is someone who is insincere or who acts one way in certain situations and then in a contrary manner in others.
An example of someone who would be described as two-faced is a person who pretends to be your friend and then starts calling you names as soon as you leave the room.
- having two faces, surfaces, etc.
- deceitful; hypocritical
- Having two faces or surfaces.
- Hypocritical or double-dealing; deceitful.
From two- +"Ž faced.