The Čudnić (Serbian Cyrillic: Чуднић) is a left, western tributary of the Vrbanja in Bosnia and Herzegovina.

It springs on the southeastern slopes of the lower Vlašić's plateau, below the Ilomska and its tributaries.

[3][4] In World War II, during Operation Kugelblitz, or the '6th Enemy Offensive', of 1943 to 1944, partisans established the 12th Division's hospital near Šiprage.

After consistent bombings of the neighboring Šiprage, about 600 injured and sick partisans were temporarily displaced to Čudnić village and other surrounding settlements on January 4, 1944.

After the departure of German and Chetnik units, this "mobile hospital" quickly returned to Šiprage (January 15, 1944).