Crossword Genius

A bit of a creature with egg hatching out (3)

Ross

I believe the answer is:

tad

'a bit' is the definition.
(both can mean a small amount)

I cannot understand how the rest of the clue works.

(Other definitions for tad that I've seen before include "Small amount or degree" , "A small amount (colloq.)" , "Little bit" , "Modest amount" , "little boy" .)

I've seen this clue in The Times.
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