Longman Dictionary of Contemporary English
Douglas Harper's Etymology Dictionary
"advocate of protecting existing things," 1905, from preservation + -ist; specifically of historic buildings by 1957.
Wiktionary
n. A person who advocates for the preservation of natural or man-made landmarks.
WordNet
n. someone who advocates the preservation of historical sites or endangered species or natural areas
Wikipedia
Preservationist is generally understood to mean historic preservationist: one who advocates to preserve architecturally or historically significant buildings, structures, objects or sites from demolition or degradation. Historic preservation usually refers to the preservation of the built environment, not to preservation of, for instance, primeval forests or wilderness.
Usage examples of "preservationist".
He cursed and redoubled his effort, expecting to hear shouts from the preservationist camp at any moment.
At that moment the shriek of a steam whistle sounded from the preservationist camp.
The most relaxed Preservationist is an order of magnitude more security-conscious than our most diligent supporter.
Or perhaps some preservationist had started the rumor in an attempt to save the houses.
Being Olivia, she immediately presented her credentials as an amateur student of old folkways and preservationist of endangered cultural treasures.
Too few are privy to the fact that the greatest danger any good preservationist may face lies within the borders of Britain herself.
If you can find out what happened to a Zoologist and Cinema Preservationist named Einar, that would be nice too.
He was interrupted by the Art Preservationist, who came thundering down the stairs, pulling on his coat.
Some of the preservationists were pouring alcohol into the tanks of a big turbine engine that squatted on the tracks like an idol to industrialism.
The preservationists pulled up short, cursing, just shy of the bushes.
Even if the Preservationists discovered a potential method for dealing with it, there was no prospect whatsoever of surrounding the entire thing with conventional machinery to administer the cure.
But the two of them had got on well enough before the separation, and Tchicaya was sick of only talking to Preservationists at the interfactional meetings, when the entire discussion was guaranteed to revolve around a mixture of procedural issues and mutual paranoia.
The Preservationists would repeat the experiments, see the same results, reach the same conclusions.
If the Preservationists had resolved to give nothing away in response to the petitioners, their own members could still get a reaction.
No percentages had been released, but the Preservationists had agreed unanimously before beginning their debate that the majority decision would be binding.