Sometimes there are words that are foreign, and a bit hard for anglophones to articulate. Such as "Dvorak", or "dvelja". When trying to refer to these words in our conversation, sometimes an extra vowel is added between the two consonants, so that it is easier to pronounce. For example, "Dvorak" is pronounced "D-ə-vo-zhak". Also, "bdellium" is pronounced "b-ə-de-llium"

Is there actually a term for this addition of vowel?