Rh negatives refers to individuals with the Rh factor absent from their blood cells. This rare blood type has several synonyms, including Rh-null, Rh-deficient, Rh-free, and Rh-incompatible. Rh-null is the rarest of all blood types, with only a few known individuals having it. It is so unique that it is often referred to as the "golden blood." Rh-deficient and Rh-free are also used synonymously with Rh negatives. Besides, Rh-incompatible may also refer to the condition where a mother's Rh-negative blood reacts with Rh-positive fetal blood during pregnancy, leading to complications. Overall, these synonyms signify the absence of Rh factor in the bloodstream.