Alphabetical list

Decussation : When a white matter tract crosses the median plane (Henle, 1855) in animals with bilateral symmetry and then assumes a longitudinal course, the crossing segment is called a decussation. The term was used in this sense at least as long ago as Collins (1685, p. 1045). Also see Nauta & Feirtag (1986, p. 82, note). more details

Deep ( Galen, c173 ) : A relationship between adjacent objects in the body; an object is deep to another when it is closer to the center; the opposite of superficial. The dichotomy has been used at least since the second century by Galen; see translation by May (1968, pp. 701, 715), also see Standring (2008, p. xxii). more details

Dendrite ( His, 1889 ) : A neuron extension that in a chain normally conducts information toward the cell body (Deiters, 1865) and/or axon (Kölliker, 1896). Most vertebrate neurons (Waldeyer, 1891) have multiple dendrites extending from the cell body whereas most invertebrate neurons have multiple dendrites extending from the axon. Dendrites were first detected by Valentin (1836; see Van der Loos, 1967, p. 26), the axon was first distinguished clearly from dendrites by Wagner (1846, see Tab. 3, Fig. 43-a; see Van der Loos, 1967, p. 37), and the dendrite was named thus by His (1889, p. 363). For vertebrates they typically branch at acute angles whereas axons branch at approximately right angles (Golgi, 1873). more details

Dendritic spine ( Cajal, 1899 ) : A short thin extension from a dendrite (His, 1889) that typically comes off at roughly a right angle. The extension may or may not have a swelling on the end; when it does, the swelling (spine head) is typically postsynaptic. They were discovered and named spines by Cajal (1888, p. 4, "espinas" in Spanish) and named dendritic spines by Cajal (1899-1904, vol. 1, Fig 14); also see Peters et al. (1991, p. 92), Alvarez & Sabatini (2007). more details

Diencephalon ( Sharpey et al., 1867 ) : Original Latin form of interbrain (Baer, 1837); p. 577. more details

Diffuse nerve net : Synonym for nerve net, though it usually implies a relative lack of marginal ganglia and nerve rings; see Bullock & Horridge (1965, p. 463). more details

Distal ( Barclay, 1803 ) : Toward the end of an object like a tentacle, limb, or nerve; opposite of proximal (Barclay, 1803). Introduced by Barclay (1803, pp. 124-125, 164), also see Standring (2008, p. xxii). more details

Division : Shortened form of topographic division. more details

Dorsal ( Barclay, 1803 ) : Toward the back of the body, or away from the belly, in the transverse plane (Henle, 1855); the opposite of ventral (Schulze, 1893); introduced formally by Barclay (1803, pp. 120, 162), who paired it with sternal. At least by the second century Galen had indicated its use, for example, in describing a direction "back toward the dorsum"; see translation by May (1968, p. 701). In Aristotle's De Partibus Animalium, there is reference to "on their [univalves] dorsal surface they have a shell"; see translation by Ogle (1912; 679b, 23-24). Also see Brusca & Brusca (1990, p. 46). more details

Dorsoventral axis : In animals with bilateral symmetry an axis orthogonal to the rostrocaudal axis that lies in the median plane (Henle, 1855); see Kuhlenbeck (1973, p. 112 and Fig. 34C-ZZ). more details

Dura ( D ; Galen, c177 ) : The outermost, toughest, and most fibrous of the three meninges (Edwin Smith Surgical Papyrus, c1700 BC); see Dorland's (2003). It was known to Hippocrates in Places in Man and Fleshes (see translation by Potter, 1995, pp. 23, 155, respectively) and named such by Galen (c177; see translation by Wiberg, 1914, p. 21). more details

Dura mater ( Ali ibn' ul-Abbas, d994 ) : Synonym for dura (Galen, c177); for naming see translation by Wiberg (1914, p. 86). more details