ar·chi·chla·myd·e·ae \|ärkēkləˈmidēˌē\noun plural Usage: capitalized Etymology: New Latin, from archi- + -chlamydeae (from Greek chlamyd-, chlamys cloak, mantle) : a group of Dicotyledoneae comprising plants in which the petals of the flowers are separate or absent — compare metachlamydeae; see apetalae, choripetalae • ar·chi·chla·myd·e·ous\| ̷ ̷ ̷ ̷ ̷ ̷| ̷ ̷ēəs\adjective