Eutheria

Eu·the·ria

noun pl \yu̇-ˈthir-ē-ə\

Definition of EUTHERIA

: a major division of mammals characterized by the attachment of the developing fetus to the maternal uterus by a placenta and including all mammals living at the present time except the marsupials

—eu·the·ri·an \-ē-ən\ adjective or noun