Computer Dictionary of Information Technology

offset

An index or position in an array, string, or block of memory usually a non-negative integer.

E.g. the Perl function splice(ARRAY, OFFSET, LENGTH, LIST) replaces LENGTH elements starting at index OFFSET in array with LIST, where offset zero means the start of the array.

For an Intel x86 processor with a segmented address space the offset is the position of a byte relative to the start of the segment.