The practice of keeping secrets.
protection from observation or surveillance.
The condition of being hidden or concealed.
Information, often secret, about an enemy or about hostile activities.
The quality of making use or having made use of such capacities: depth of understanding, mental quickness.
A political or military department, agency or unit designed to gather information, usually secret, about the enemy or about hostile activities.
Capacity of mind, especially to understand principles, truths, facts or meanings, acquire knowledge, and apply it to practice; the ability to comprehend and learn.
An entity that has such capacities.