What is the proper noun of scientist?

There isn't a single proper noun for "scientist". Proper nouns are specific names for people, places, or things. "Scientist" is a common noun, describing a general category of people.

To make it a proper noun, you'd need to specify a particular scientist, like:

* Albert Einstein

* Marie Curie

* Dr. Jane Goodall

Let me know if you'd like to know more about scientists or have other questions!