Research questions fall into three categories: descriptive, predictive, or causal. In the last decade, there have been calls for the proper use of causal language for causal research questions. Nevertheless, it is common for researchers with causal questions to use non-causal language - approximately 56% to 9% of random journals have articles with causal aims, but the research question itself used non-causal language such as "association", "risk factor" or "associated with". The article explains why using causal language to express a causal research question is essential, rather than just preferable. It also provides clear guidance on the correct use of frequently misused terms such as "causal effect," "association," and "estimated causal effect" in research articles and in relation to specific quantities.