syncarpous

As a verb joined

is (join).

As an adjective syncarpous is

(botany|of a pistil) having carpels joined together.

As a noun carpel

is one of the individual female reproductive organs in a flower a carpel is composed of an ovary, a style, and a stigma, although some flowers have carpels without a distinct style in origin, carpels are leaves (megasporophylls) that have evolved to enclose the ovules the term pistil is sometimes used to refer to a single carpel or to several carpels fused together.

As an adjective syncarpous is

(botany|of a pistil) having carpels joined together.