back up
v.
1767, "stand behind and support," from back, v. + up. The noun meaning "a standby, a reserve" is recorded from 1952 (often written as one word, backup); specific reference to computing is from 1965.
| 词汇 | back up |
| 词根词缀 | Online Etymology Dictionary back up v. 1767, "stand behind and support," from back, v. + up. The noun meaning "a standby, a reserve" is recorded from 1952 (often written as one word, backup); specific reference to computing is from 1965. |
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