1. 
   Red Letter
   Red Letter is a cultivated variety of potato.
   Found op http://www.probertencyclopaedia.com/browse/QR.HTM
   
   
2. 
   Red-letter
   Red'-let`ter adjective Of or pertaining to a red letter; marked by red letters. Red-letter day , a day that is fortunate or auspicious; -- so called in allusion to the custom of marking holy days, or saints' days, in the old calendars with red...
   Found op http://www.encyclo.co.uk/webster/R/31
   
   
3. 
   red-letter
   adjective memorable for being a special occasion; `on red-letter nights a large gathering greeted the celebrity`
   Found op http://wordnetweb.princeton.edu/perl/webwn?s=red-letter
   
   
4. 
   Red-letter
   • (a.) Of or pertaining to a red letter; marked by red letters.
   Found op http://thinkexist.com/dictionary/meaning/red-letter/
   
   
5. 
   Redletter
   Exclusive, breaking news coverage of a major news event, printed in red type.
   Found op http://www.journalism.co.uk/terms-definitions-dictionary-terminology-words/
   
   
6. 
   redletter
   An important breaking news story. From the newspaper practice of highlighting an exclusive, breaking news story in red type.
   Found op http://www.thenewsmanual.net/Resources/glossary.html
   
   
7. 
   redletter
   1) Important, in a way 2) Memorable
   Found op http://www.mijnwoordenboek.nl/EN/crossword-dictionary/redletter/1
   
   

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