late 13c. distourben, "to frighten, alarm, break up the tranquility of;" c. 1300, "to stop or hinder;" from Old French destorber (Old North French distourber) and directly from Latin disturbare "throw into disorder," from dis- "completely" (see dis-) + turbare "to disorder, disturb," from turba "turmoil" (see turbid). Related: Disturbed; disturbing; disturbingly.
Middle English also had the verb as distourblen, from Old French destorbler; hence also distourbler (n.) "one who disturbs or incites" (late 14c.).
"to loosen and throw about in disorder, cause to have a disordered or neglected appearance," 1590s, said originally of the hair, later of the dress. It is chiefly a back-formation from disheveled (q.v.).
genetic disorder causing developmental and intellectual delays, 1961, from J.L.H. Down (1828-1896), English physician; chosen as a less racist name for the condition than earlier mongolism.
"a physical disorder or disease," late 13c., maladie, from Old French maladie "sickness, illness, disease" (13c.), abstract noun from malade "ill" (12c.), from Late Latin male habitus "doing poorly, feeling sick," literally "ill-conditioned," from Latin male "badly" (see mal-) + habitus, past participle of habere "to have, hold" (from PIE root *ghabh- "to give or receive"). Extended sense of "moral or mental disorder, disordered state or condition" is from 14c. Related: Maladies.
1776, "throw into confusion, disturb the regular order of," from French déranger, from Old French desrengier "disarrange, throw into disorder," from des- "do the opposite of" (see dis-) + Old French rengier (Modern French ranger) "to put into line," from reng "line, row," from Frankish *hring or some other Germanic source, from Proto-Germanic *hringaz "circle, ring, something curved," from nasalized form of PIE root *sker- (2) "to turn, bend." Mental sense "disorder or unsettle the mind of" is by c. 1790.