Spider coming from altar — aunt going giddy (9)

I believe the answer is:

tarantula

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

'spider' is the definition.
(tarantula is a kind of spider)

'altar aunt going giddy' is the wordplay.
'altar aunt' can be anagrammed to 'TARANTULA'.
Though, I am unsure how this is indicated.

'coming from' is the link.

Can you help me to learn more?

(Other definitions for tarantula that I've seen before include "Creepy-crawly" , "Breed of spider" , "A large hairy tropical spider" , "small, venomous creature" , "A big hairy spider" .)

I've seen this clue in The Times.

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