castellanus

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• IPA^(key): /ˌkæstəˈlɑːnəs/

castellanus (plural castellani)

1. (meteorology) A cloud species which shows vertical formations giving a crenellated appearance, associated with cirrus, cirrocumulus, altocumulus, and stratocumulus genera.
   • 1985 February 14, Dennis Wheeler, “Saharan dust storm over England”, in New Scientist‎, volume 105, number 1443, page 26:

     Turbulent mixing, evidenced by alto-cumulus castellanus cloud over France, also took place en route and carried dust to high altitudes.

   • 1993, Monthly Weather Review - Volume 121, Issues 10-12, page 2709:

     Over France the altocumuli castellani clouds at medium level indicate a very unstable air mass there, because these clouds often develop into thunderstorms.

   • 1998, Stuart H. Walker, The Sailor's Wind‎, page 56:

     But liftoff in warm, moist, unstable air in which condensation is occurring may result in an updraft capped by a towering altocumulus castellanus cloud at 11,000 to 15,000 feet.

   • 2011, Gavin Pretor-Pinney, The Cloud Collector's Handbook‎, page 40:

     When a layer of cloud rises in distinct turrets with bumpy tops that resemble crenellations, it is of the species known as castellanus—and this one can give an early indication of unsettled weather to come later in the day.

2. Alternative form of castellan
   • 1979, Adolf M. & Kaegi Hakkert (Walter E.), Byzantinische Forschungen - Volume 6, page 17:

     In addition to the rettori, there were castellani of the fort in the town of Chios and of fourteen other forts in the society's island. The castellanus of the urban fort was chosen by a complicated process of indirect election resembling that which determined the Podestà, and again like him was to be drawn from the popolari of Genoa.

   • 1998, Guillaume IX ((duc d'Aquitaine ;), ‎Ralph Henry Carless Davis, & ‎Marjorie Chibnall, The Gesta Guillelmi of William of Poitiers, page xli:

     Castle garrisons are castellani; WP does not use the term oppidani.

   • 2001, Adam J. Kosto, Making Agreements in Medieval Catalonia, →ISBN:

     In these documents conderning the castle of Talarn, however, the term castellanus is applied to both of the bottom two levels of the hierarchy: the texts imply that both Oliver Bernat and Guillem Folc are castellani.

• AMS Glossary of Meteorology

castellum +‎ -ānus.

castellanus (feminine castellāna, neuter castellānum)

1. of or pertaining to a fort or castle[1]

castellanus (plural castellānī)

1. (usually in plural form) the occupants of a castle[2]