The term 'experimental group' is a commonly used phrase in research and scientific experimentation. But sometimes, writers need to expand their vocabulary and find other words to use instead of it. Here are some synonym options; treatment group, study group, intervention group, action group, subject group, intervention treatment group, and test group. These terms convey the same meaning and can be used interchangeably. Therefore, when crafting academic papers or reports, writers need to have a range of synonyms that they can use to avoid repetitive phrases and make their work more interesting and engaging for readers.