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.
