Definition of Dyad

1. Bad Bugs and Their Bites Slideshow
2. Heartburn: Foods to Eat and Avoid Slideshow
3. Understanding Multiple Sclerosis Slideshow

Dyad: The word "dyad" comes from the Greek "dyas" meaning the number two.

In psychology, a dyad refers to a pair of persons in an interactional situation. For example, a patient and therapist, a woman and her husband, a girl and her stepfather, etc.

In chemistry, a dyad is a bivalent element. And in biology, a dyad is a double chromosome resulting from the splitting of a tetrad (a quadruple chromosome) during meiosis (germ cell formation).

Need help identifying pills and medications?
Use the pill finder tool on RxList.