Sentence:  This threat, the reader may well suppose, was not very <WSD>tranquilizing</WSD> to my feelings. 
Meaning of the word marked with <WSD> tags:  To make (something or someone) tranquil.<ref>(Thomas Blount), "Glossographia," London: George Sawbridge, 1661: “"Tranquillize" (...) to make quiet, still or calm, to cause tranquility.”[http://name.umdl.umich.edu/A28464.0001.001]</ref>