A lone soldier is someone who has come to Israel on his or her own, deliberately to join the Israel Defense Forces. There are about 5000 Jewish lone soldiers in the IDF. Last week, Fadi Abad Alhallik from Brazil became the first Druze lone soldier when he returned to the land of his birth and joined up.
http://www.idfblog.com/blog/2012/02/07/family-firsts-meet-first-ever-druze-lone-soldier/