Sandhi

Sandhi (Sanskrit: sandhi "joining") is a cover term for a wide variety of phonological processes that occur at morpheme or word boundaries (thus belonging to morphophonology). Examples include the fusion of sound across word boundaries, as its name implies, and the alteration of sounds from nearby sounds or the grammatical function of adjacent words.

Sandhi occurs particularly prominently in the phonology of Indian languages (especially Sanskrit, Telugu Marathi, Hindi, Pali, Kannada, Bengali). However, it exists in many other languages, such as in some North Germanic languages.

Sandhi can be either internal, within words at morpheme boundaries, as (syn- + pathy); or external, at word boundaries, such as in the pronunciation tem books for ten books in some dialects of English. The linking /r/ of some dialects of English is a kind of external sandhi, as is the process called liaison in French and raddoppiamento fonosintattico in Italian, a process known in English as syntactic gemination.

It may be extremely common in speech, but sandhi (especially external) is typically ignored in spelling, as is the case in English, except for the distinction between a and an. Sandhi is, however, reflected in the orthography of Sanskrit, Telugu, Marathi, Pali and some other Indian languages, as with in Italian in the case of compound words with lexicalized syntactic gemination.

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