MRCT – The people in a study who do not receive the study treatment or do not have the condition being studied.
https://mrctcenter.org/glossaryterm/control-group/
CDISC-Gloss – The group of subjects in a controlled study that receives, for example, no treatment, a standard treatment, or a placebo. [21 CFR 314.126] See also control, controlled study, arm (protocol).