What is "adnation"

Adnation \Ad*na"tion\, n. (Bot.) The adhesion or cohesion of different floral verticils or sets of organs.

n. (context botany English) The adhesion or cohesion of different floral verticils or sets of organs.

Adnation in plants is the "union of unlike parts; organically united or fused with another dissimilar part, e.g. stamens to petals". This is in contrast to connation, the fusion of similar organs.