Attachment of the surface of one part to that of another part; the condition of being adnate; especially the union of one whorl of floral organs to another dissimilar whorl, as stamens to petals.
((n.) The adhesion or cohesion of different floral verticils or
sets of organs.)
Origin:
Mid 19th century; earliest use found in Asa Gray (1810–1888), botanist. From adnate + -ion; compare -ation.