A self-propelled separable element of a rocket vehicle or spacecraft.

A circuit containing a single section of an electron tube or equivalent device or two or more similar sections connected in parallel, push-pull, or push-push; it includes all parts connected between the control-grid input terminal of the device and the input terminal of the next adjacent stage.

1. A developmental phase of an erosion cycle in which landscape features have distinctive characteristic forms.

2. A phase in the historical development of a geologic feature.

3. A major subdivision of a glacial epoch.

4. A time-stratigraphic unit ranking below series and above chronozone, composed of rocks formed during an age of geologic time.

The elevation of the water surface in a stream as measured by a river gage with reference to some arbitrarily selected zero datum. Also knonw as stream stage.

1. A certain length of underground roadway worked by one horse.

2. A narrow thin dike, especially one where the material of which the dike is composed is soft.

3. A platform on which mine cars stand.