un·writ·ten 
(ŭn-rĭtn)
(ŭn-rĭtn)adj.
1. Not written or recorded: an unwritten agreement between friends.
2. Having authority based on custom, tradition, or usage rather than doctrine: an unwritten law.
3. Not written on; blank.
- silver chloride
- silver cord
- silverfish
- silver fox
- silveriness
- silver iodide
- silver lining
- silver maple
- silver mound
- silvern
- silver nitrate
- silver perch
- silver plate
- silver-plate
- silverpoint
- silver protein
- silverrod
- silver salmon
- silver screen
- silverside
- silversides
- silversmith
- silver spoon
- silverspot
- silver standard