Contraction was a change caused by a loss of "j" between vowels and their merging into one long vowel, for example "dobroje" → "dobré" (good) and "bojati sę" → "báť sa" (to be afraid). The contraction originated in the territory of Great Moravia in the last years of its existence and divided the Slavic territory into contraction and non-contraction areas. In Proto-Slovak, the contraction occurred before the disappearance and vocalization of yers, but not uniformly. In later Western and Eastern Slovak dialects, the change was similar to other West Slavic languages. The Central Slovak shares some old features with the South-Slavic contraction peripheral territory. The Central Slovak preserved more non-contracted forms (i.e. "moja", "moje" vs. "má", "mé", "bojati sa" /dialect/ vs "báť sa"). The different process of contraction "oje" → "oe" → "ô" probably resulted also to the characteristic neuter adjective ending "-ô" (i.e. "dobrô" vs. "dobré").