Alternative etymology: Nightshade

Deadly nightshade (Atropa belladonna) is a highly toxic hallucinogen. Its cousin, the black nightshade (Solanum nigrum) is also supremely poisonous.

The deadly nightshade is native to temperate southern and central Europe, but has been cultivated and introduced outside its native range. Its most northern frontier reaches Skåne in Sweden, where it was grown in apothecary gardens.

Yes, The deadly nightshade is one of the most toxic plants found in the Eastern hemisphere (though it has been introduced in the Western hemisphere). On the other hand, the ripe berries and cooked leaves of the black nightshade are used in traditional medicine.

Right. The botanicals are now sorted. So where does the name 'nightshade' derive from?

The Etymology Dictionary predictably claims that Old English nihtscada literally means 'shade of night'. Yes, both in Dutch and German the same word is used for these plants: nachtschade (Dutch) and Nachtschatten (German). The Dictionary suggests that the name is perhaps an allusion to the poisonous black berries. A similar Swedish word was nattskata which meant a 'bat'. Even in Ancient Greek, 'bat' (νυκτερίς), derived from 'night' (νύξ). Bats were (and still are) shadows in the night.

So, nightshadow it or isn't it? In modern Dutch 'schade' means damage. Modern Frisian skea has exactly the same meaning. That directs us to an alternative explanation of the word 'nightshade': the plant has berries that are as black as the night and these cause damage.