From a diachronic standpoint, grammaticalisation is commonly defined as a part of the natural process of language change, where, under certain circumstances, various lexical items and linguistic elements turn into different forms to serve grammatical functions. Over a substantial amount of time, some free morphemes such as nouns and verbs obtain new grammatical tasks becoming modals, case markers, auxiliary verbs, postpositions, connectives etc. Through grammaticalisation, new morphological forms come to represent certain semantic structures that lack morphological and phonetic representation on the surface. As this kind of language change takes place on the one hand, the same nouns and verbs continue to function as free morphemes keeping their original linguistic meanings and assignments intact, on the other. This process is observed in several languages worldwide independent of their genetic affinity. Various forms of grammaticalisation can be observed in Turkish as well. The aim of this study is to identify the elements and look into some forms of grammaticalisation observed both in Turkish and some other world languages. The study also aims to make a contribution to the employment of this term in Turkology studies.