Animal to put lb1 on? (4)

I believe the answer is:

lion

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'animal' is the definition.
(I know that lion is a type of animal)

'lb1 on?' is the wordplay.
'lbl' becomes 'li' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'li'+'on'='LION'

'to put' is the link.

Can you help me to learn more?

(Other definitions for lion that I've seen before include "Simba, for example" , "Important figure" , "British RU cap" , "Touring rugby player" , "King of the jungle" .)

I've seen this clue in the Evening Standard.

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