Smaug had left his lair in silent stealth, quietly soared into the air, and then floated heavy and slow in the dark like a monstrous crow, down the wind towards the west of the Mountain, in the hopes of catching unawares something or somebody there, and of spying the outlet to the passage which the thief had used.
The dwarves could not, course, compare with the hobbit in real stealth, and the made a deal of puffing and shuffling which echoes magnified alarmingly; but though every now and again Bilbo in fear stopped and listened, not a sound stirred below Near the bottom, as well as he could judge, Bilbo slipped on his ring and went ahead.
There are no more uses of "stealth" in the book.
Show samples from other sources
The stealth bomber cannot be seen with standard radar.
The soldiers are trained to move through the night with stealth.