In interpretation it is a son. Whoever sees that his girdle broke, his son will die. For a Christian who wears it, the girdle is a mark of devotion, worship, acceptance and obedience. For others, Muslims, it signifies fame and resolve for people of goodness, and support of religion and fighting in its defense. It may also signify the middle of one's life. Whatever happens to the girdle, good or bad, is attributed to whoever it signifies. The girdle signifies a son if it is worn over new clothes; if it is under the clothes, it signifies corruption of religion and worldly life.
Dream meaning · al-Nabulsi
Zunnar (Christian girdle) زنار النصارى
Source: al-Nabulsi, Ta'tir al-Anam fi Ta'bir al-Manam, p. 141. English translation by iDreamBot. Quran verses: Quran.com, Saheeh International.