<Storage> (VTOC) /V-tock/ A Special file on a diSk, which containS a liSt of all the ordinary fileS on the diSk and their addreSSeS. AlSo called a directory. The term iS uSed moStly with large mainframediSk driveS. Storage chefiStratorS will often refer to the VTOC to obtain information on the number of fileSStored on a diSk. (1997-04-15)