What is the function of a stigma in plants?

The function of the stigma in a flower is as a pollen receptor. The stigma is a sticky tip on the top of a carpel.

The stigma is contained inside of the pistil, which also contains the ovary, style and carpel. A pistil may have several carpels. The style is the part of the flower, also called a stalk, that allows pollen tubes to grow from grain. These tubes become part of the stigma and helps it to receive the pollen. The carpel and its other parts can often be referred to as the gynoecium, a Greek word meaning "woman's house."