The term "non-functional" refers to things that do not work properly or do not fulfill their purpose. Some synonyms for this term include dysfunctional, useless, ineffective, deficient, and malfunctioning. These words can be used interchangeably to describe objects or systems that are not working as they should. For example, a non-functional computer may be described as a dysfunctional or malfunctioning computer. Similarly, a useless or ineffective tool may be referred to as a non-functional or deficient tool. It is important to use synonyms in writing and communication to avoid repetition and make the text more varied and interesting.