Being motherly makes little material difference (8)

I believe the answer is:

maternal

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

'being motherly' is the definition.
('maternal' can be similar in meaning to 'motherly')

I don't understand how the remainder of the clue works.

(Other definitions for maternal that I've seen before include "Of a mother or motherhood" , "Motherly" , "On the mother's side" , "Protective" .)

I've seen this clue in the Evening Standard.

Want a hint initially instead of a full solution? Install my app