fin defined in 1951 yearfin - fin;
fin - Of aquatic vertebrates: Median f. in mid-line of body, unpaired, either continuous, or as separate dorsal, caudal (which functions in propulsion of fish) or ventral fins. Paired fins are lateral: pectoral attached to shoulder-girdle, pelvic attached to pelvic girdle; these two pairs, homologues of tetrapod limbs though they do not contain comparable bones, occur in most fish but not in Agnatha; their usual function is control of direction of movement.
near fin in Knolik
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