Erectile (adjective)

1. Capable of becoming rigid or stiff, especially with an influx of blood.
2. Capable of being raised up or stiffened.

Origin:

From latin erectus ("upright") + -ile.

Examples:

1. The penis has an erectile tissue that enables it to become stiff during sexual arousal.
2. The plant's leaves have an erectile capacity that enables them to face towards the sun.
3. The feathers of the bird have an erectile ability that allows it to change its shape for flight.
4. The antennae of the insect have an erectile ability that enables it to sense its environment.
5. The fins of the fish have an erectile property that enables them to change direction while swimming.