Poker face is a common phrase used to refer to someone who is emotionally detached and keeps their feelings hidden from others. However, there are other synonyms that can be used to describe this type of behavior such as stoic, reserved, impassive, expressionless, blank, unemotional, or unflappable. Each of these terms describes an individual who remains calm, collected, and unreactive to stressful or emotionally charged situations. A person with an unflappable demeanor tends to give little indication of their inner thoughts or emotions, making it difficult to know what they are feeling or thinking at any given time. These synonyms can be used interchangeably with poker face to describe someone who has mastered the art of hiding their emotions.