Celestial objects for boys, say (4)

I believe the answer is:

suns

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

'celestial objects' is the definition.
'Suns' can be an answer for 'objects' (Sun is an example). I am unsure of the 'celestial' bit.

I cannot understand how the rest of the clue works.

Can you help me to learn more?

(Other definitions for suns that I've seen before include "Stars" , "Sources of light and heat for the planets" .)

I've seen this clue in The Mirror.

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