Stoneface is a word that refers to someone who has a facial expression that is difficult to interpret. It can also mean someone who is cold, indifferent, or emotionless. Some other synonyms for the word stoneface include pokerface, blank-faced, expressionless, and stoic. These words have different nuances or shades of meaning but all share a common idea of a lack of expression on a person's face. Other related words might include unemotional, impassive, or unflappable, which describe a person's demeanor, rather than just their facial expression. All of these words can be useful for describing characters in literature, or for talking about real people who display these traits.