master boot record

(redirected from Partition sector)

master boot record

The first sector on the hard disk, which contains a tiny program and the disk's partition table. When the program is executed, it determines which partition contains the active operating system and branches to the boot program in that partition's boot sector to load it. See boot sector.
References in periodicals archive ?
Virus A program or code that replicates--that is, infects another program, boot sector, partition sector, of document that supports macros by inserting itself or attaching itself to that medium.