- Allergic rhinitis: the clinical term for what we often call “hay fever”, a collection of physical symptoms that includes itchy, inflamed eyes and runny nose.
- Catkins: a slim, flowery, pollen-producing cluster that grows on a variety of trees and shrubs, including birch, willow, and hickory.
- Cross-reactivity: a phenomenon in which the proteins of one substance closely resemble those of another.
- Dander: tiny scales of hair, feathers, or skin released by animals, which may be allergenic.
