Triquetrous is a unique word that describes something that has three corners or angles. However, there are several other words that can be used as synonyms for this term. These include triangular, trilateral, three-sided, trefoil, and trigonal. Each of these words describes something that also has three corners or angles, but they can be used in different contexts depending on the situation. For example, irregular objects with three angles may be called triquetrous, while objects with equilateral triangles can be called trigonal or triangular. Overall, these synonyms provide various options for describing objects with three corners or angles and can be used interchangeably to add variety and depth to your language.