This is the 3976th most frequent Russian word.
изюм
Raisins.
Here, 'изюм' is used to refer to the edible dried grapes as a food item.
Я купил пакет изюма в магазине.
I bought a packet of raisins at the store.
In this context, 'изюм' denotes raisins as an ingredient in a dish, adding distinct flavor.
Изюминка этого пирога — добавление изюма.
The highlight of this pie is the addition of raisins.
In this metaphorical use, 'изюм' represents something valuable or outstanding within a specific context.