||Pa*ta"gi*um (?), n.; pl. Patagia (#). [L., an edge or border.] 1. (Anat.) In bats, an expansion of the integument uniting the fore limb with the body and extending between the elongated fingers to form the wing; in birds, the similar fold of integument uniting the fore limb with the body.

2. (Zoöl.) One of a pair of small vesicular organs situated at the bases of the anterior wings of lepidopterous insects. See Illust. of Butterfly.