(physics) A mathematically defined region around an atomic nucleus defined by a high probability that the atom's electrons will be present in that region.

(meteorology) A low, horizontal cloud typically forming at the leading edge of thunderstorm outflow. An arcus type cloud often found along squall lines.

(meteorology) Grouping of the standard cloud classification system. Members include cirrus, cirrocumulus, cirrostratus, altocumulus, altostratus, nimbostratus, stratocumulus, stratus, cumulus, and cumulonimbus.

A subgrouping of standard cloud classification system, coming after the major cloud genera

plural of cloud genus

(meteorology) An accessory cloud in the form of a cap which occurs above, or attached to, cumulus, cumulonimbus, and sometimes stratocumulus clouds.

(meteorology) A small cloud formation which is found attached to, or close by, a major cloud of one of the cloud genera, which is responsible for its development and continuance.

(meteorology) a small cloud that remains stationary and is related to a geographical feature, such as a mountain. Classified as banner clouds, cap clouds, crest clouds, or lenticular clouds http://amsglossary.allenpress.com

(meteorology) a small, triangular cloud, extending downwind from the peak of a mountain as if a flag, or banner.

(meteorology) a standing cloud, extending downwind from a mountain range, or ridge.