Top of birthday cake tapers (7)

I believe the answer is:

candles

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'tapers' is the definition.
('candle' can be a synonym of 'taper')

I cannot understand how the remainder of the clue works.

Can you help me to learn more?

(Other definitions for candles that I've seen before include "They're held by sconces" , "Wax lights" , "They illuminate" , "Tealights, for example" , "Sticks of wax with wicks" .)

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

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