chlamydo-, chlamyd- (Greek: cloak, mantle; envelope).

clamydia, a sexually transmitted disease that's the leading cause of preventable infertility. Chlamydia is found mostly among young adults and adolescents. It has no symptoms in 70 percent or more of females, and more than 50 percent of males. It comes from a bacterium called Clamydia Trachomatis.