Goddess of unnamed cereals (5)

I believe the answer is:

ceres

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'goddess' is the definition.
(I know that Ceres is a goddess)

I don't understand how the rest of the clue works.

(Other definitions for ceres that I've seen before include "Roman goddess; dwarf planet" , "chief of agriculture" , "She fills granaries" , "Circling rock" , "The largest asteroid" .)

I've seen this clue in the Evening Standard.

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