Go To Ground Meaning

Example : 1912, H. Rider Haggard, Marie, ch. 19:  I heard them on the other bank, and then saw a man on a horse crossing the river, and went to ground like a jackal.1906, Arthur Griffiths, The Passenger from Calais, ch. 11:  It was more than enough for my fugitives to clear out of the Lausanne station and make some new move, to hide away in an out-of-the-way spot, go to ground in fact, or travel in another direction.2008, Vivienne Walt, "France's $7.2 Billion Hit," Time, 24 Jan.:  Kerviel's identity was revealed on the Financial Times and Daily Telegraph websites, but was not confirmed by bank officials, who admitted on Thursday that the rogue trader appeared to have gone to ground and that they had no idea where he was.