stratio-, strati-, strato-, strat- stratus

1. In meteorology, a principal cloud classification, characterized by gray or white, usually stratiform layers that nearly always have dark patches and a nonfibrous aspect; usually arranged in orderly groups, lines, or waves, and composed of small water droplets, sometimes accompanied by larger droplets, soft hail, and (rarely) snowflakes.
2. A cloud formation in a low-lying extensive layer with large dark round or rolling masses.

The boundary layer between the stratosphere and the mesosphere, at around 30 miles/50 km above the Earth's surface

A telescope that operates by remote control and is lifted by balloon to high altitudes so as to reduce the effect of atmospheric turbulence on the observations.

1. The region of the Earth's atmosphere between the troposphere and mesosphere, from 6 miles/10 km to 30 miles/50 km above the Earth's surface. It has no clouds and is marked by gradual temperature increases.
2. In former use, it referred to all of the atmosphere above the troposphere.
3. A very high or the highest level or position.
4. The nearly uniform cold ocean water masses in high latitudes and near-bottom waters of middle and low latitudes; ocean water below the thermocline.

In geology, the sequence of strata that was originally described for a given location, and that serves as a standard against which other parts of the stratigraphic unit are compared.

A reference to clouds.

1. A volcano consisting of layers of lava alternating with ash or cinder.
2. A volcano that is composed of alternating layers of lava and pyroclastic material, along with abundant dikes and sills. Viscous, intermediate lava may flow from a central vent. Example: Mt. Fuji in Japan.

1. Any of several parallel layers or levels of something.
2. A layer of the atmosphere or the sea.
3. In biology, a layer of living cells; or a layer, i.e., a sheetlike mass of substance of nearly uniform thickness, especially when the layer is one of several associated layers, as in tissue.
4. A horizontal layer of vegetation within a stratified plant community.
5. A social class or level of society consisting of people of similar cultural, economic, or educational status.
6. A layer or level within an ordered system.

Layer; layers.

1. A low-lying flat gray cloud formation.
2. In meteorology, a principal cloud genus characterized by a gray layer having a relatively uniform base; often occurring in the form of ragged patches or fragments (stratus fractus) and usually composed of fairly widely dispersed water droplets; similar to stratocumulus, but lower and lacking the latter's uniform relief.

The lowest layer of the Earth's atmosphere, at a height of about 12 miles/20 km above the Earth.