[treated as sing.]a contagious disease of tropical countries, caused by a bacterium that enters skin abrasions and gives rise to small crusted lesions which may develop into deep ulcers 雅司病。 亦称 framboesia
The bacterium is the spirochaete Treponema pallidum subsp. pertenue 细菌为螺旋菌苍白密螺旋体细长亚种
语源
late 17th cent.: probably from Carib yaya, from a South American Indian language