Diglossia
Diglossia is a sociolinguistic situation in which two varieties of the same language (or two closely related languages) coexist in a community, each serving distinct social functions. The term was formalised by Charles Ferguson (1959) in his foundational paper "Diglossia" in Word.
High and Low Varieties
Ferguson identified two varieties:
| Feature | High (H) variety | Low (L) variety |
|---|---|---|
| Function | Formal settings: education, government, religion, literature, news | Informal settings: daily conversation, family, marketplace |
| Acquisition | Learned through formal education | Acquired naturally as mother tongue |
| Standardisation | Codified grammar, dictionaries, literary canon | Largely uncodified; may lack a standard written form |
| Prestige | High — associated with education, culture, authority | Low — associated with informality, intimacy, solidarity |
| Stability | Highly stable — diglossic situations can persist for centuries | Stable in speech; may be under pressure from H in media |
Classic Examples
| Community | H variety | L variety |
|---|---|---|
| Arabic-speaking countries | Modern Standard Arabic (fusha) | Regional dialects (aamiya/darija) |
| Switzerland (German) | Standard German (Hochdeutsch) | Swiss German (Schwyzerdütsch) |
| Haiti | French | Haitian Creole |
| Greece (historical) | Katharevousa | Demotic Greek |
Ferguson's Nine Features
Ferguson characterised diglossia through nine defining features:
- Function — specialised distribution of H and L across domains
- Prestige — H is valued more highly
- Literary heritage — H has a prestigious literary tradition
- Acquisition — L is learned at home; H in school
- Standardisation — H has formal grammar and dictionaries
- Stability — the situation persists over long periods
- Grammar — H typically has more complex morphology (case systems, verb inflections)
- Lexicon — paired vocabulary items (H and L words for the same concept)
- Phonology — H and L have related but distinct phonological systems
Extended Diglossia (Fishman, 1967)
Joshua Fishman broadened the concept beyond varieties of the same language to include situations where two unrelated languages serve H and L functions — for example, Spanish (H) and Guarani (L) in Paraguay, or English (H) and local languages (L) in many postcolonial contexts.
This extended sense is directly relevant to ELT: in many World Englishes contexts, English functions as an H variety alongside local L varieties.
Relevance to ELT
- In many teaching contexts (Vietnam, the Gulf states, parts of Africa), students live in diglossic or extended diglossic environments where English occupies a specific functional niche
- Understanding diglossia helps explain learner attitudes — students may value English (H) for instrumental purposes while maintaining strong affective ties to their L variety
- Register awareness connects directly: learners navigating between H and L must develop sensitivity to when each variety is appropriate
- Code-Switching between H and L varieties is a natural feature of diglossic communities, not a sign of deficiency
- Language planning decisions (see Language Planning and Policy) directly shape whether a community is diglossic and how H/L boundaries evolve