Psychologists have outlined several subtle indicators that may suggest someone secretly dislikes another person. These signs, published in BBC Science Focus, include avoiding eye contact, which might be an attempt to create psychological distance.
More convincing signs reportedly include facial expressions that convey contempt or disgust. Other potential indicators are smiling less around a particular individual, their body pointing away, and creating physical distance.
However, a disclaimer notes that reduced eye contact, physical distance, and less smiling can also be attributed to various factors such as tiredness, shyness, neurodiversity, anxiety, distraction, or cultural norms. This suggests that it can be difficult to definitively determine if someone secretly dislikes another person based solely on these behaviours.