Affixes

A pathogen (Greek gen‑, root of gignomai, be born, become) is a bacterium, virus, or other micro-organism that can cause disease; pathology is the science of the causes and effects of diseases; the adjective pathological refers to a physical or mental disease, but sometimes has the sense of somebody compulsive or obsessive; pathogenesis is the manner of development of a disease; pathognomonic (Greek gnōmōn, judge) refers to a sign or symptom that indicates a particular disease or condition. Pathos, a quality that evokes pity or sadness, and pathetic, arousing pity, come from the same source.