psyllid yellows

noun plural but singular or plural in construction

: a virus disease of potatoes characterized by rolling and yellowish discoloration of the leaflets and transmitted by the potato psyllid

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