randomyoudaoicibaDictYouDict[random 词源字典]
random: [14] The antecedents of random are somewhat murky. It originally meant ‘impetuosity, sudden speed, violence’, and only in the mid 17th century emerged as an adjective meaning ‘haphazard’. It was borrowed from Old French randon, which was probably a derivative of the verb randir ‘run impetuously’. This in turn was based on Frankish *rant ‘running’, which was apparently descended from prehistoric Germanic *randa.

This originally meant ‘edge’ (it is the source of English rand [OE], now obsolete as a term for ‘edge’, but reintroduced in the 20th century via Afrikaans as the name of the basic South African currency unit), but it was also widely used for ‘shield’, and it is thought that the link with ‘running impetuously’ may be the notion of soldiers running along with their shields.

=> rand[random etymology, random origin, 英语词源]
random (adj.)youdaoicibaDictYouDict
"having no definite aim or purpose," 1650s, from at random (1560s), "at great speed" (thus, "carelessly, haphazardly"), alteration of Middle English noun randon "impetuosity, speed" (c. 1300), from Old French randon "rush, disorder, force, impetuosity," from randir "to run fast," from Frankish *rant "a running" or some other Germanic source, from Proto-Germanic *randa (cognates: Old High German rennen "to run," Old English rinnan "to flow, to run;" see run (v.)).

In 1980s U.S. college student slang it began to acquire a sense of "inferior, undesirable." (A 1980 William Safire column describes it as a college slang noun meaning "person who does not belong on our dormitory floor.") Random access in reference to computer memory is recorded from 1953. Related: Randomly; randomness.