These are the meanings of the letters SETR- when you unscramble them.
            
                
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                    Erst (adv.)
                    
                        First.
                    
                 
                
                - 
                    Erst (adv.)
                    
                        Previously; before; formerly; heretofore.
                    
                 
                
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                    Rest (n.)
                    
                        A place where one may rest, either temporarily, as in an inn,   or permanently, as, in an abode.
                    
                 
                
                - 
                    Rest (n.)
                    
                        A projection from the right side of the cuirass, serving to   support the lance.
                    
                 
                
                - 
                    Rest (n.)
                    
                        A set or game at tennis.
                    
                 
                
                - 
                    Rest (n.)
                    
                        A short pause in reading verse; a c/sura.
                    
                 
                
                - 
                    Rest (n.)
                    
                        A state of quiet or repose; a cessation from motion or labor;   tranquillity; as, rest from mental exertion; rest of body or mind.
                    
                 
                
                - 
                    Rest (n.)
                    
                        A surplus held as a reserved fund by a bank to equalize its   dividends, etc.; in the Bank of England, the balance of assets above   liabilities.
                    
                 
                
                - 
                    Rest (n.)
                    
                        Hence, freedom from everything which wearies or disturbs;   peace; security.
                    
                 
                
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                    Rest (n.)
                    
                        Silence in music or in one of its parts; the name of the   character that stands for such silence. They are named as notes are,   whole, half, quarter,etc.
                    
                 
                
                - 
                    Rest (n.)
                    
                        Sleep; slumber; hence, poetically, death.
                    
                 
                
                - 
                    Rest (n.)
                    
                        That on which anything rests or leans for support; as, a rest   in a lathe, for supporting the cutting tool or steadying the work.
                    
                 
                
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                    Rest (n.)
                    
                        That which is left, or which remains after the separation of   a part, either in fact or in contemplation; remainder; residue.
                    
                 
                
                - 
                    Rest (n.)
                    
                        The striking of a balance at regular intervals in a running   account.
                    
                 
                
                - 
                    Rest (n.)
                    
                        Those not included in a proposition or description; the   remainder; others.
                    
                 
                
                - 
                    Rest (n.)
                    
                        To be free from whanever wearies or disturbs; to be quiet or   still.
                    
                 
                
                - 
                    Rest (n.)
                    
                        To be satisfied; to acquiesce.
                    
                 
                
                - 
                    Rest (n.)
                    
                        To cease from action or motion, especially from action which   has caused weariness; to desist from labor or exertion.
                    
                 
                
                - 
                    Rest (n.)
                    
                        To lean in confidence; to trust; to rely; to repose without   anxiety; as, to rest on a man's promise.
                    
                 
                
                - 
                    Rest (n.)
                    
                        To lie; to repose; to recline; to lan; as, to rest on a   couch.
                    
                 
                
                - 
                    Rest (n.)
                    
                        To sleep; to slumber; hence, poetically, to be dead.
                    
                 
                
                - 
                    Rest (n.)
                    
                        To stand firm; to be fixed; to be supported; as, a column   rests on its pedestal.
                    
                 
                
                - 
                    Rest (v. i.)
                    
                        To be left; to remain; to continue to be.
                    
                 
                
                - 
                    Rest (v. t.)
                    
                        To arrest.
                    
                 
                
                - 
                    Rest (v. t.)
                    
                        To lay or place at rest; to quiet.
                    
                 
                
                - 
                    Rest (v. t.)
                    
                        To place, as on a support; to cause to lean.
                    
                 
                
                - 
                    rets (unknown)
                    
                        Sorry. I don't have the meaning of this word.
                    
                 
                
                - 
                    tres (unknown)
                    
                        Sorry. I don't have the meaning of this word.