modern word "vampire" derives from the Old Slavic and Turkic form "онпыр" (onpyr), with the addition of the sound "v-" before a large nasal vowel (on), characteristic...

Proto-Slavic. The addition of the "v" sound to the Old Slavic form "онпыр" (onpyr) in front of the large nasal vowel (on) is characteristic of Old Bulgarian...