{"era":"current","word":"invaluable","meaning":"having such great value that it cannot be measured","children":[{"era":"current","word":"in- + valuable","meaning":"not + valuable","children":[{"era":"1300s","word":"valuable","meaning":"worth a lot","children":[{"era":"1200s","word":"value","meaning":"worth, value","children":[{"era":"1200s","word":"valeur","meaning":"value, worth","children":[{"era":"classical","word":"valēre","meaning":"to be strong, to be worth","children":[],"language":"Latin"}],"language":"Old French"}],"language":"Middle English"}],"language":"English"}],"language":"Modern English"}],"language":"Modern English"}