What is the meaning of ʋ?

a voiced labiodental approximant.

[ʋ]-coloring, such as a rhotacized vowel Vᶹ in some dialects of English; or a weak, fleeting or epenthetic [ʋ]. It might be used more specifically for 'secondary reduction of the lip opening accompanied by neither protrusion nor velar constriction.'

labiodentalization (a type of [ʋ]-coloring), e.g. [sᶹ], [zᶹ] and [ɹᶹ] for some individuals in English.

a voiced bilabial fricative; superseded by β

A letter of the Choctaw alphabet.

A letter of the Ewe alphabet.

A letter of the Moore alphabet.

Source: wiktionary.org