An alveolar tap /ɾ/ is made by tapping the alveolar ridge with the tip of the tongue (directly above its resting position). For an alveolar trill /r/, the tip of the tongue is made to vibrate so that it taps the alveolar ridge multiple times. So /ɾ/ is like a very short version of /r/.

A labiodental tap /ⱱ/ is also a tap, but it is created in a different position. It is made with the lower lip and upper teeth (hence "labiodental"), not the tongue. It sounds partway between /b/ and /v/ (and /ʋ/) but weaker. The voiced labiodental fricative /v/ is also made with the lower lip and upper teeth, but differs because it is a fricative. This means that it is made by constricting the flow of air between them, creating sound through friction.

The labiodental tap /ⱱ/ also differs from the voiced bilabial stop /b/ in two ways. /b/ is a stop rather than a tap. It is a much stronger action that completely (though briefly) blocks the flow of air through the mouth. In addition, /b/ is made with both lips (hence "bilabial") and not the teeth.