allocation unit

English Thesaurus

1. a group of sectors on a magnetic disk that can be reserved for the use of a particular file (noun.quantity)

hypernym	:	computer memory unit,
definition	:	a unit for measuring computer memory (noun.quantity)

part holonym	:	sector,
definition	:	the minimum track length that can be assigned to store information; unless otherwise specified a sector of data consists of 512 bytes (noun.quantity)