1. Plural of cumulonimbus; large, towering clouds that produce thunderstorms, heavy rain, hail, and sometimes tornadoes.
Usage: meteorology; Also called thunderstorm clouds or storm clouds

Examples

• The meteorologist warned that several cumulonimbuses were developing over the plains.
• Dark cumulonimbuses towered above the landscape, signaling an approaching severe storm.
• Pilots avoid flying through cumulonimbuses due to the dangerous turbulence and lightning.
• The cumulonimbuses produced torrential rain and hail across the region.
• Weather radar detected multiple cumulonimbuses forming along the cold front.
• These massive cumulonimbuses can reach heights of over 40,000 feet.