There are a total of 24 4-letter words containing 'vo', and the number may vary in different dictionaries. You can specify the dictionary and order.

• arvo ₈
• avos ₈
• avow ₁₁
• levo ₉
• novo ₉
• vivo ₁₂
• voce ₁₁
• voes ₈
• void ₉
• voir ₈
• voix ₁₅
• vole ₉
• volk ₁₃
• volt ₉
• vote ₈
• vows ₁₁
• vogs ₈
• evoe ₇
• evos ₇
• rivo ₇
• voar ₇
• vola ₇
• vols ₇
• vors ₇

There are 24 4-letter words containing vo in the well-known word game dictionary, 12 in the Scrabble US (US/Canada/Thailand - TWL/NWL) dictionary, and 19 in the Scrabble UK (International - SOWPODS/CSW) dictionary, and 16 in the Words with Friends (WWF) dictionary.