Grind down queen with poem (5)

I believe the answer is:

erode

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

'grind down' is the definition.
(I know that grind down can be written as erode)

I don't understand the rest of the clue.

Can you help me to learn more?

(Other definitions for erode that I've seen before include "'Deteriorate, wear away (5)'" , "fragment" , "Gradually destroy" , "Grind down" , "Slowly remove" .)

I've seen this clue in The Mirror.

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