{"era":"current","word":"playground","meaning":"children's play area","children":[{"era":"12th century","word":"play","meaning":"to engage in activity for enjoyment","children":[{"era":"pre-1100","word":"plegian","meaning":"to move rapidly, to sport","children":[],"language":"Old English"}],"language":"Modern English"},{"era":"pre-1100","word":"ground","meaning":"the surface of the earth","children":[{"era":"pre-1100","word":"grund","meaning":"bottom, earth","children":[],"language":"Old English"}],"language":"Modern English"}],"language":"Modern English"}