Aqua. Water.

Areola. A circle around the nipple.

Areolar tissue. The tissue that connects various compound parts of the body.

Articulation. The joining or union of bones.

Artery. A vessel carrying blood from the heart.

Ascarides. Pin worms.

Ascites. Abdominal dropsy.

Asphyxia. Apparent death; suspended animation.

Assimulation. The process by which nutriment is converted into the substance of the body.

Asthenia. Want of strength; exhaustion; debility.