sociology of language
Academic field studying the relationship between language and society, focusing on how social factors influence language use and structure.
From the perspective of the sociology of language, we analyzed changes in dialects.
sociolinguistics
Often used interchangeably with 社会言語学, though some scholars distinguish the two. In practice, both refer to the study of language in its social context.
See also: 社会言語学
彼は言語社会学（社会言語学）の専門家だ。
He is a specialist in sociolinguistics.