{"era":"current","word":"unseen","meaning":"not seen or not visible","children":[{"era":"pre-1100","word":"un-","meaning":"not; opposite of","children":[],"language":"Old English"},{"era":"1200s","word":"seen","meaning":"perceived by sight","children":[{"era":"pre-1100","word":"see","meaning":"to perceive with the eyes","children":[],"language":"Old English"},{"era":"pre-1100","word":"-en","meaning":"past participle ending","children":[],"language":"Old English"}],"language":"Middle English"}],"language":"Modern English"}