pelvic fin

US /ˈpel.vɪk fɪn/
UK /ˈpel.vɪk fɪn/
"pelvic fin" picture
1.

pinna pelvica, pinna ventrale

either of a pair of fins on the underside of a fish's body, typically behind the pectoral fins, that help control direction and stability

:
The fish used its pelvic fins to maintain balance in the current.
Il pesce ha usato le sue pinne pelviche per mantenere l'equilibrio nella corrente.
Sharks have two pelvic fins located near their cloaca.
Gli squali hanno due pinne pelviche situate vicino alla loro cloaca.