Refers to a sweet liquid, often in a poetic or figurative sense, such as the nectar of flowers or a drink of the gods. Also used metaphorically for something exquisitely sweet or delightful.
The nectar of this flower is truly like ambrosia.
honeydew
Specifically refers to honeydew, the sweet secretion produced by aphids and some scale insects. This is a technical or biological use.
Aphids secrete honeydew onto the leaves.
His words soaked into my heart like sweet nectar.
candied chestnuts; sweet-simmered chestnuts · sweet-simmered fish; fish candied in soy and sugar
From Chinese 甘露 (gānlù), literally 'sweet dew'. The term originally referred to a sweet dew believed to fall from heaven as an auspicious sign, and later extended to nectar, honeydew, and figurative sweetness.