The term 'is litigious' refers to someone or something that is prone to taking legal action. The crossword solutions for this term are SUS (3 letters) and SUES (4 letters). The verb 'SUE' means to initiate a legal action against someone, and the verb 'sus' is an abbreviation of the word 'SUSPECT', which means to have an idea or belief that something is true without having proof. Therefore, the term 'is litigious' can be interpreted as someone or something that is likely to take legal action against another person or entity.