Effective. To be efficient.

Element. One part of a whole.

Elasticity. Material which will go back to its original form after being distorted, is said to be elastic.

Eliminate. To take away from; to remove a part, or the whole.

Elliptical. Oblong with rounded ends.

Elusive. Capable of escaping from; hard to hold.

Elevator. The horizontal planes in front or rear, or in both front and rear of the supporting surfaces of an aeroplane.

Emergency. A sudden occurrence calling for immediate action.

Emplacement. A spot designed to hold heavy field pieces in intrenchments.

Enactment. The formulation of a law; the doing of a special thing.