In Western Europe, the fruit was often depicted as an apple. This was possibly because of a misunderstanding of – or a pun on – two unrelated words mālum, a native Latin noun which means ‘evil’ (from the adjective malus), and mâlum, another Latin noun, borrowed from Greek μῆλον, which means ‘apple’. In the Vulgate, Genesis 2:17 describes the tree as “de ligno autem scientiae boni et mali”: “but of the tree [literally ‘wood’] of knowledge of good and evil” (mali here is the genitive of malum). There is nothing in the Bible indicating that the forbidden fruit of the tree of knowledge was an apple.[10]
I think apple used to be a generic term for fruits.
It is especially apparent for exotic fruits, for example here is a list of fruits from the Caribbean, none of then are related to the European apple:
My German professor even mentioned the archaic apfelsine for the citrus orange.
Apfelsine is not archaic. Very widely used today, at least here in the south.
Also, it literally means “Chinese apple” lol
Apelsin in Sweden
Potato (Pomme de Terre, Erdapfel)
In a slavic language (either Croatian or Czech, I forgot), it’s krompir, literally ground/soil pear.
It can, but I’m not sure if that explains why it’s often represented as an apple in the west.
Here’s what Wikipedia has to say: