black thread

noun

: a disease of the tapped area of the Para rubber tree that is caused by a fungus (Phytophthora meadii) and that is characterized by black lines extending through the exposed bast into the cambium or wood

called also black stripe, stripe canker

The Ultimate Dictionary Awaits

Expand your vocabulary and dive deeper into language with Merriam-Webster Unabridged.

1. Expanded definitions
2. Detailed etymologies
3. Advanced search tools
4. All ad-free

Discover what makes Merriam-Webster Unabridged the essential choice for true word lovers.

Start Your Free Trial Now