v-row katakana (ヴ)

Katakana ヴ and its small-vowel companions ヴァ・ヴィ・ヴェ・ヴォ used to approximate the /v/ sound in foreign words — ヴァイオリン (violin), ベートーヴェン (Beethoven). A modern addition (postwar) to the katakana inventory; some newer writing prefers the simpler バ-row, treating /v/ as /b/.