The act of calling ( troops) into active service.
- The Winston Simplified Dictionary. By William Dodge Lewis, Edgar Arthur Singer. Published 1919. (noun) (n.) (noun)
Act of mobilizing.
- Nuttall's Standard dictionary of the English language. By Nuttall, P.Austin. Published 1914. (noun) (n.) (noun)

Usage examples:

Mobilization ordered throughout the Empire.
- England and Germany by Emile Joseph Dillon
In vain Russia protested that her partial mobilization was merely a precaution.
- America's War for Humanity by Thomas Herbert Russell
I knew that the speech of the governor would be about the State militia and I knew that Evan Baldwin would talk to them about the mobilization of their stocks and crops.
- The Golden Bird by Maria Thompson Daviess