"Aspecular" is a scientific term used to describe a surface or object that does not reflect light in any direction or has no specular reflection. Some synonyms for "aspecular" include non-reflective, matte, dull, rough, and absorbent. These words can be used to describe objects that do not have a shiny or reflective surface, such as a matte finish on a car, a rough rock, or a non-shiny fabric. Additionally, the word "opaque" can also be used to describe a surface that does not allow light to pass through it, which is a type of aspecular behavior. Overall, these synonyms describe a lack of reflective properties and how light interacts with the surface of an object.