Squarrose. Having spreading and projecting processes, such as the tips of involucral scales.

Squarrulose. Diminutively squarrose.

Stamen. One of the pollen-bearing or fertilizing organs of the flower.

Staminodium. A sterile stamen, or any structure without anther corresponding to a stamen.

Standard. The upper dilated petal of a papilionaceous corolla.

Stellate, Stelliform. Star-shaped.

Stem. The main ascending axis of a plant.

Sterile. Unproductive, as a flower without pistil, or stamen without an anther.

Stigma. That part of a pistil through which fertilization by the pollen is effected.

Stigmatic. Belonging to or characteristic of the stigma.