Clear a chessboard, taking great pains? No, little ones (8)

I believe the answer is:

earaches

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'no little ones' is the definition.
Although both the answer and definition are plural nouns, I don't understand how one could define the other.

'clear a chessboard taking great pains?' is the wordplay.
'EARACHES' is hidden in amongst the letters.
However, I'm uncertain how this is indicated.

Can you help me to learn more?

I've seen this clue in The Telegraph.

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