A supporter of placing restrictions on something (noun)
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Use "restrictionist" in a sentence
"Biophilia I did not like the term restrictionist because I felt that the idea of a spirit and/or soul was not restricting."
"ROMANS: Congressman J.D. Hayworth has been called a restrictionist for not supporting the president's guest worker program and pushing for tougher border enforcement."
"UNIDENTIFIED MALE: I personally don't think that's a very accurate use of the word "restrictionist," but words that have those ethical connotations always tend to be used in these context, precisely because they are so loaded."