cumulonimbus

IPA/ˌkjuːmələʊˈnɪmbəs/
IPA/ˌkjuːmələʊˈnɪmbəs/

cumulonimbus — noun

1. A very tall, dark cloud that rises high into the sky and brings storms with heav

1.nounC1
Definition

A very tall, dark cloud that rises high into the sky and brings storms with heavy rain, thunder, lightning, or hail.

Example

A large cumulonimbus cloud formed over the plain, bringing heavy rain.

collocation: cumulonimbus + formed over [place]

The pilot flew the plane around the tall cumulonimbus to avoid rough weather.

Common collocations
  • cumulonimbus cloud
  • cumulonimbus formation
  • towering cumulonimbus
  • cumulonimbus incus
  • develop into a cumulonimbus
Synonyms
  • thundercloud

    more general, everyday term; less precise scientifically

  • storm cloud

    even broader; can refer to any dark cloud that brings storms

  • anvil cloud

    describes the flat-topped shape of a mature cumulonimbus

Antonyms
  • cirrus

    a thin, wispy high-altitude cloud with no rain

Grammar Patterns

cumulonimbus + cloud

cumulonimbus + [verb]

Usage Note

Often followed by 'cloud' or 'clouds' in everyday use ('a cumulonimbus cloud'). Can also stand alone as a countable noun ('A large cumulonimbus appeared on the horizon'). Common in weather forecasts and meteorological descriptions rather than everyday conversation.

Common Mistakes

A cumulonimbus is a kind of storm.
A cumulonimbus is a kind of cloud that often produces storms.
cumulonimbus names the cloud type, not the storm itself.

Word family

  • cumulus
    nounC1
  • nimbus
    nounC2
  • nimbostratus
    nounC2

Synonym discussion

Sense: noun/1

While 'cumulonimbus' is the precise meteorological term for a tall, dark cloud that produces thunderstorms, 'thundercloud' and 'storm cloud' are everyday alternatives that speakers use more loosely. A thundercloud is always a cumulonimbus, but not every cumulonimbus necessarily produces thunder at the moment you see it. 'Nimbostratus' is a different rain cloud — it is low, flat, and produces steady drizzle rather than sudden downpours with lightning. 'Anvil cloud' describes the distinctive flat-top shape of a mature cumulonimbus that has reached the tropopause. When you see a towering, dark mass with an anvil-shaped top approaching, you are looking at a cumulonimbus — and it is time to take cover.

thundercloud ↗storm cloud ↗nimbostratusanvil cloud

Common collocations

Nouns

Adverbs

Phrases

  • develop into a cumulonimbus
  • cumulonimbus on the horizon

Prepositions

Etymology

LatinEnglish

From Latin 'cumulus' meaning 'heap' or 'pile' and 'nimbus' meaning 'rain cloud'. The term was adopted in the late 19th century as part of the international cloud classification system developed by meteorologists Luke Howard and Ralph Abercromby. Howard had used 'cumulus' and 'nimbus' separately decades earlier; their combination names the cloud that piles up highest and brings the most violent weather.