charcoal rot

noun

: a disease of plants that is common in the southern U.S. and destructive to sweet and white potatoes and to corn and is caused by a fungus (Macrophomina phaseoli) which attacks the lower stem and roots destroying much of the tissues and forming myriads of tiny black sclerotia on what remains

Love words?

You must — there are over 200,000 words in our free online dictionary, but you are looking for one that’s only in the Merriam-Webster Unabridged Dictionary.

Start your free trial today and get unlimited access to America's largest dictionary, with:

• More than 250,000 words that aren't in our free dictionary
• Expanded definitions, etymologies, and usage notes
• Advanced search features
• Ad free!