Source : Webster's Revised Unabridged Dictionary (1913)

Interleaf \In"ter*leaf`\, n.; pl. {Interleaves}. [See
   {Interleave}.]
   A leaf inserted between other leaves; a blank leaf inserted,
   as in a book.

Source : WordNet®

interleaf
     n : a blank leaf inserted between the leaves of a book
     [also: {interleaves} (pl)]

Source : Free On-Line Dictionary of Computing

Interleaf
     
        A document preparation system for {Sun}, {VAX}, {Apollo} and
        other {workstations}.
     
        (1994-11-09)