Meaning of black dolphin in English:
black dolphin
noun
1(More fully "black dolphin fly") a black aphid, a blackfly; specifically the bean aphid, Aphis fabae; (now rare).
2Any of several marine dolphins (family Delphinidae) with black skin; especially the long-finned pilot whale, Globicephala melas, and the Chilean dolphin, Cephalorhynchus eutropia.
Origin
Mid 18th century; earliest use found in William Ellis (c1700–1758), agriculturist and writer.
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