di-, dicho-, dich-

(Greek: number two; twice, divided, double; unalike; a number used as a prefix)

Occurring in two phases or stages.
The production of two different tones when speaking; also called double voice.
diplacusis (s) (noun), diplacuses (pl)
1. The hearing of the same sound differently by one ear than by the other one so that a single sound is perceived as two: As a musician, Jasper realized that the displacusis from which he suffered was getting progressively worse and he realized that he would need to change careers if his condition could not be cured.

Iris thought she was losing her mind when she first developed diplasusis, because she was concerned that she was hearing duplicate sounds when she was sure she only should have heard just one.

2. Etymology: from Greek dipl-, "two fold, double" + akousis, "hearing".
diplanetism (s) (noun), diplanetisms (pl)
A condition whereby there are two periods of motility or movement that is spontaneous without external aid which is usually applied to a microorganism in one lifetime: The zoospores of some fungi are examples of diplanetisms.
diplobiont (s) (noun), diplobionts (pl)
Vegetation which has flowers and bears fruit two times a year: Such diplobionts, as some brown algae and fungi, have life-cycles known as gametic meiosis.
diploid (adjective), more diploid, most diploid
A reference to possessing two matched sets of chromosomes in the cell nucleus of a child, one set contributed by each parent: Diploid organisms include almost all mammals, having two complements of chromosomes which contain chemical compositions that control what an animal is like.
diploma (s) (noun), diplomas (pl)
1. A certificate that has been given by a school, college, or university which verifies that someone has completed a certain course of study or has graduated after a certain amount of education: After going to high school and finishing all of the required subjects with good grades, Jackie received her high school diploma and now she can apply for admission to the nearby college.
2. A document that grants certain rights, privileges, honors, etc.: A diploma, or certificate, signed by a king in historical contexts, verified a grant or tenure of a defined piece of land and its conditions.
3. Etymology: from Greek > Latin diploma, "paper folded double".
diplopiaphobia (s) (noun), diplopiaphobias (pl)
An exaggerated anxiety of having double vision: Diplopiaphobia can be a result of a feeling of losing one's control of the environment, and is perhaps caused by a muscle imbalance or to a paralysis of certain eye muscles.
In medicine, a developmental anomaly involving complete or incomplete duplication of a foot.
dipody, dipodous, dipodic
A double foot; two feet.