While on official posting in Chennai in 1976, Mr Khaire started studying Tamil. Almost from the start it became clear to him that contrary to accepted theory, many Marathi words have cognates in Tamil. They were words in nursery rhymes, in old poetry and inscriptions, names of cults and practices, words for body parts and kinship terms, words in the kitchen and farming... in short in all walks of life. Many of the Tamil words were similar to those in the Marathi dialect of the village in which he grew up. Derivation of these Marathi words from Sanskrit was not called for. Initially, these findings were published in a series of short articles in popular style. These were later published with extensive linguistic and cultural notes in book form. A book explaining meanings of place-names in Maharashtra on the basis of Tamil was also published in 1977, in which he showed that place-names in inscriptions were sanskritised forms of names in local speech.

He also revealed words in old Tamil literature comparable to Marathi words. In one essay he referred to Caldwell, Max Mueller and Molesworth to show that the Aryan-Dravidian dichotomy based on languages is not sustained if Marathi is taken into account. He has considered the development of Marathi vocabulary, grammar, etc. were from both Sanskrit and Tamil sides and based on these studies, proposed the hypothesis of deep relationship of Samskrit-Marathi-Tamil (Sammata) in the book Marathi Bhasheche Mula (Origin of Marathi). In papers presented to Linguistics conferences, he has discussed the comparative phonetic values of Tamil alveolars in Marathi vocabulary, Marathi cognates of words chosen to illustrate Dravidian phonology, as well as a proposal for an Indian Etymological Dictionary combining the Dravidian and Indo-Aryan dictionaries of Burrow-Emeneau and Turner.