from The American Heritage® Dictionary of the English Language, 4th Edition
- n. The swollen upper portion of a thundercloud, usually associated with the development of a thunderstorm.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. The top portion of a cumulonimbus cloud, which tend to be flattened or fibery in appearance, and which may be indicative of thunderstorm activity.
from the GNU version of the Collaborative International Dictionary of English
- n. A rounded mass of cloud, with shining white edges; a cumulus, -- often appearing before a thunderstorm.
from The Century Dictionary and Cyclopedia
- n. One of the round compact swelling cumulus clouds which frequently develop into thunder-clouds.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a rounded projecting mass of a cumulus cloud with shining edges; often appears before a thunderstorm
Sorry, no etymologies found.