semiotician; symbolist
Refers to a scholar who studies signs and symbols, especially in the field of semiotics. The gloss 'symbolist' is less common and may refer to a practitioner of symbolism in art or literature; the primary meaning is a semiotician.
As a semiotician, he studies the role of signs in culture.
記号論 is the field of semiotics, while 記号論学者 is a person who studies it.
Compound of 記号 (sign, symbol), 論 (theory, discourse), and 学者 (scholar). The term is a straightforward academic compound.