Barricade yourself in
Definition 1 of 2
Pro Tip 1/3Physical Action
Refers to using objects to physically prevent entry. 
When he heard the commotion outside, he quickly barricaded himself in his room with furniture.
Pro Tip 2/3Immediate Safety
Used in emergencies to create a safe zone. 
The survivors had to barricade themselves in the basement to stay safe from the hurricane.
Pro Tip 3/3Temporary Measure
Suggests a short-term solution, not permanent. 
During the protest, shopkeepers barricaded themselves in their stores until calm was restored.