linguist
A scholar who studies linguistics; a neutral, academic term.
He is a famous linguist.
To become a linguist, you need to do research in graduate school.
言語学 is the field of linguistics, while 言語学者 refers to a person who studies it.
語学者 often means a scholar of a specific language or philologist, whereas 言語学者 is a broader term for a linguist.
Compound of 言語 (language) + 学 (study) + 者 (person). A straightforward kanji compound meaning 'one who studies language'.