Noun
someone who makes something attractive to the general public
Source: WordNetI'm sometimes asked how I would like to be remembered. I've had a diverse career as a writer, underwater explorer, space promoter and science populariser. Of all these, I want to be remembered most as a writer - one who entertained readers, and, hopefully, stretched their imagination as well. Arthur C. Clarke
The original populariser of Marxism in Russia, Georgi Plekhanov used the terms "dialectical materialism" and "historical materialism" interchangeably. Source: Internet
He was also a populariser of mathematics and physics and wrote several books for the lay public. Source: Internet