標題の ethnomethodology （エスノメソドロジー）は，1967年にアメリカの社会学者 Harold Garfinkel の作り出した用語であり，言語コミュニケーションに関する社会学的なアプローチを指す．日常会話の基礎となる規範，しきたり，常識を探ることを目的とする．人類言語学 (anthropological linguistics)，社会言語学 (sociolinguistics)，会話分析 (conversation analysis)，おしゃべりの民族誌学 (ethnography_of_speaking) などの領域と重なる部分があり，学際的な分野である．Trudgill の社会言語学用語辞典より，関連する4つの用語の解説を与えたい．
ethnomethodology A branch of sociology which has links with certain sorts of sociolinguistics such as conversation analysis because of its use of recorded conversational material as data. Most ethnomethodologists, however, are generally not interested in the language of conversation as such but rather in the content of what is said. They study not language or speech, but talk. In particular, they are interested in what is not said. They focus on the shared common-sense knowledge speakers have of their society which they can leave unstated in conversation because it is taken for granted by all participants.
ethnography of speaking A branch of sociolinguistics or anthropological linguistics particularly associated with the American scholar Dell Hymes. The ethnography of speaking studies the norms and rules for using language in social situations in different cultures and is thus clearly important for cross-cultural communication. The concept of communicative competence is a central one in the ethnography of speaking. Crucial topics include the study of who is allowed to speak to who --- and when; what types of language are to be used in different contexts; how to do things with language, such as make requests or tell jokes; how much indirectness it is normal to employ; how often it is usual to speak, and how much one should say; how long it is permitted to remain silent; and the use of formulaic language such as expressions used for greeting, leave-taking and thanking.
ethnography of communication A term identical in reference to ethnography of speaking, except that nonverbal communication is also included. For example, proxemics --- the study of factors such as how physically close to each other speakers may be, in different cultures, when communicating with one another --- could be discussed under this heading.
conversation analysis An area of sociolinguistics with links to ethnomethodology which analyses the structure and norms of conversation in face-to-face interaction. Conversation analysts look at aspects of conversation such as the relationship between questions and answers, or summonses and responses. They are also concerned with rules for conversational discourse, such as those involving turn-taking; with conversational devices such as discourse markers; and with norms for participating in conversation, such as the rules for interruption, for changing topic, for overlapping between one speaker and another, for remaining silent, for closing a conversation, and so on. In so far as norms for conversational interaction may vary from society to society, conversation analysis may also have links with cross-cultural communication and the ethnography of speaking. By some writers it is opposed to discourse analysis.
ethnomethodology は，言語の機能 (function_of_language) という深遠な問題にも疑問を投げかける．というのは，ethnomethodology は，言語をコミュニケーションの道具としてだけではなく，世界を秩序づける道具としてもとらえるからだ．Wardhaugh (272) 曰く，"people use language not only to communicate in a variety of ways, but also to create a sense of order in everyday life."
・ Trudgill, Peter. A Glossary of Sociolinguistics. Oxford: Oxford University Press, 2003.
・ Wardhaugh, Ronald. An Introduction to Sociolinguistics. 6th ed. Malden: Blackwell, 2010.