Arm

Matthias Löbe added this term as an example for SNOMED CT concepts. SNOMED CT hat no textual definitions but a formal hierarchy.

Caveat: This term is part of the SNOMED CT US Extension, not of SNOMED International. SNOMED CT doesn't cover a lot of the terms of research management. Additionally, it is debatable whether the classification as observable entity fits at all or it differs from clinical trial group (social concept).