Ardha-Magadhi
The most archaic of the Middle Indo-Aryan languages are the inscriptional Aśokan Prakrit on the one hand and Pāli and Ardhamāgadhī ("Half Magadhi") on the other, both literary languages.
The Indo-Aryan languages are commonly assigned to three major groups – Old, Middle and New Indo-Aryan. The classification reflects consecutive stages in a common linguistic development, but is not merely a matter of chronology: Classical Sanskrit, as a codified derivate of Vedic Sanskrit, remains mostly representative of the Old Indo-Aryan stage, even though it continued to flourish at the same time as the Middle Indo-Aryan languages. Conversely, a number of the morphophonological and lexical features of the Middle Indo-Aryan languages betray the fact that they may not be direct continuations of Ṛgvedic Sanskrit, the main base of Classical Sanskrit; rather they descend from other very similar Old-Indo-Aryan dialects which some regard as probably even more archaic than Rigvedic.
MIA languages, though individually distinct, share features of phonology and morphology which characterize them as parallel descendants of Old Indo-Aryan. Various sound changes are typical of the MIA phonology:
(1) The vocalic liquids 'ṛ' and 'ḷ' are replaced by 'a', 'i' or 'u'; (2) the diphthongs 'ai' and 'au' are monophthongized to 'e' and 'o'; (3) long vowels before two or more consonants are shortened; (4) the three sibilants of OIA are reduced to one, either 'ś' or 's'; (5) the often complex consonant clusters of OIA are reduced to more readily pronounceable forms, either by assimilation or by splitting; (6) single intervocalic stops are progressively weakened; (7) dentals are palatalized by a following '-y-'; (8) all final consonants except '-ṃ' are dropped unless they are retained in 'sandhi' junctions.
The most conspicuous features of the morphological system of these languages are: loss of the dual; thematicization of consonantal stems; merger of the f. 'i-/u-' and 'ī-/ū-' in one 'ī-/ū-' inflexion, elimination of the dative, whose functions are taken over by the genitive, simultaneous use of different case-endings in one paradigm; employment of 'mahyaṃ' and 'tubhyaṃ' as genitives and 'me' and 'te' as instrumentals; gradual disappearance of the middle voice; coexistence of historical and new verbal forms based on the present stem; and use of active endings for the passive. In the vocabulary, the MIA languages are mostly dependent on Old Indo-Aryan, with addition of a few so-called 'deśī' words of (often) uncertain origin.
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