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early 14c., "throw down or fall with force," perhaps from a Scandinavian source (cf. Danish dumpe, Norwegian dumpa "to fall suddenly"). The sense of "unload en masse" is first recorded in American English 1784. That of "discard, abandon" is from 1919. Related: Dumped; dumping. Dump truck is from 1930.
"place where refuse is dumped," 1865, originally of mining operations, from dump (v.). Meaning "any shabby place" is from 1899. Meaning "act of defecating" is from 1942.
[origin uncertain; perhaps related to a Scandinavian term meaning ''to fall suddenly,'' the connection being the tipping out of a load from a cart]
1. An undigested and voluminous mass of information about a problem or the state of a system, especially one routed to the slowest available output device (compare core dump), and most especially one consisting of hexadecimal or octal runes describing the byte-by-byte state of memory, mass storage, or some file. In elder days, debugging was generally done by "groveling over" a dump (see grovel); increasing use of high-level languages and interactive debuggers has made such tedium uncommon, and the term "dump" now has a faintly archaic flavour.
2. A backup. This usage is typical only at large time-sharing installations.
Unix manual page: dump(1).