All nasal clicks have twin airstreams, since the air passing through the nose bypasses the tongue. Usually this is pulmonic egressive. However, the series in Taa is characterized by pulmonic "ingressive" nasal airflow. Ladefoged & Maddieson (1996:268) state that "This ǃXóõ click is probably unique among the sounds of the world's languages that, even in the middle of a sentence, it may have ingressive pulmonic airflow." Taa is the only language known to contrast voiceless nasal and voiceless nasal aspirated (i.e. delayed aspirated) clicks (Miller 2011).