Listen for a soft nicker. The unicorn nickered and walked forward. -- Gwen Perkins, "The Hunt" (2006) A nicker is produced when a unicorn uses its vocal chords to create a vibrating sound with its mouth closed. The technique is similar to that practiced by ventriloquists, but unicorns usually achieve less vulgar results. A unicorn's gentle nicker can indicate recognition and express pleasure. It can also be questioning: Something made a questioning sound out in the brush, and he looked up warily. Glowing yellow eyes looked at him before their owner vanished with a rustle. (Angela Knight, Master of the Night, 2004) Soft nickers can also sound: comforting beckoning like a low chuckle contented