Is an 'ideolect' peculiar to just one person, or are there national/communal 'ideolects'?

Question

The OED definition of idiolect (see below), would suggest it is something personal. but I have seen it used, including on this site as a word which describes the common idiomatic content of a community. It is used like dialect but referring specifically to idioms. This post for example talks about the Indian idiolect.

So does the OED reflect the way the word is used or not?

The linguistic system of one person, differing in some details from that of all other speakers of the same dialect or language.

1948 B. Bloch in Language 24 7 The totality of the possible utterances of one speaker at one time in using a language to interact with one other speaker is an idiolect.

1964 M. A. K. Halliday et al. in J. A. Fishman Readings Sociol. of Lang. (1968) 158 A person's idiolect may be identified, through the lens of the various registers, by its grammatical and lexical characteristics.

1975 R. L. Williams Ebonics p. vi, Ebonics..includes the various idioms, patois, argots, ideolects, and social dialects of black people.

2001 S. S. Mufwene Ecol. Lang. Evol. viii. 193 Every new speaker replicates their target communal language imperfectly, starting with the trivial fact that they couldn't possibly replicate all the idiolects of which it is an ensemble and no idiolect replicates another.

Answer 1

Both its origin and current usage suggest that it is a term specific just to a personal way of speaking; from idio- meaning one's, personal:

An idiolect:

• is a person’s specific, unique way of speaking. Every one of us has his or her very own idiolect that differs from the way other people talk.

• A dialect is a version of a language spoken by a group of people. An idiolect is much smaller — it’s the way a particular person speaks, at a specific time, as distinct from others.

• This word is mainly used by linguists when discussing differences in speech from one person to another. Like your fingerprint, your idiolect is unique. It’s kind of like a micro-dialect. (www.vocabulary.com)

Idiolect: etymology:

• one's personal way of using a language, 1948, from idio- "one's own, personal" + second element abstracted from dialect. Idioglottic (1888) has a sense "using words invented in one's mind" (from Greek glotta/glossa "tongue"). (Etymonline)

From Britannica,com

Dialect:

• ...denotes rural or provincial dialects, often with a deprecatory connotation. A similar term is vernacular, which refers to the common, everyday speech of the ordinary people of a region. An idiolect is the dialect of an individual person at one time. This term implies an awareness that no two persons speak in exactly the same way and that each person’s dialect is constantly undergoing...

individual speech habits:

• ...that may impede but do not prevent mutual comprehension are called dialects of a language. In order to describe in detail the actual different speech patterns of individuals, the term idiolect, meaning the speech habits of a single person, has been coined.