What beats a card symbol? (5)

I believe the answer is:

heart

I'm a little stuck... Click here to teach me more about this clue!

'card symbol?' is the definition.
'heart' can be an answer for 'card' (the hearts are a playing card suit). I am unsure of the 'symbol?' bit.

I cannot understand how the rest of the clue works.

Can you help me to learn more?

(Other definitions for heart that I've seen before include "Kernel" , "Muscular organ for blood circulation" , "See 22" , "Core; organ" , "Body organ" .)

I've seen this clue in the Sydney Morning Herald.

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