megabyte

noun Computers.

1. 220 (1,048,576) bytes.
2. (loosely) one million bytes. Abbreviation: MB

noun

1. computing 2 20 or 1 048 576 bytesAbbreviation: MB, mbyte See also mega- (def. 2)

n.1972, from mega- + byte. The Sussex team has run the Forrester/Meadows models more than 1000 times on the UK’s most powerful computer (the giant two-megabyte IBM 370/165 at Harwell). [“New Scientist,” May 4, 1972]

1. A unit of computer memory or data storage capacity equal to 1,048,576 bytes (1,024 kilobytes or 220 bytes).
2. One million bytes.

A unit of computer information: one million bytes.