The Collaborative International Dictionary
                    Unsufferable
                    
                        
                
                                                                    Unsufferable \Un*suf"fer*a*ble\, a.
   Insufferable. [Obs.] 
--Hooker. --  Un*suf"fer*a*bly, adv.
Wiktionary
                    unsufferable
                    
                        
                
                                                                    a. Not able to be suffered, difficult or impossible to endure; insufferable.
WordNet
                    unsufferable
                    
                        
                
                                                                    adj. used of persons or their behavior; "impossible behavior"; "insufferable insolence" [syn: impossible, insufferable, unacceptable]
Usage examples of "unsufferable".
In a village near the last of these places I had the curiosity to go and see their way of living, which is most brutish and unsufferable.