Ordinary sensible understanding; one's basic intelligence which allows for plain understanding and without which good decisions or judgments cannot be made.
Capacity of mind, especially to understand principles, truths, facts or meanings, acquire knowledge, and apply it to practice; the ability to comprehend and learn.
The quality of making use or having made use of such capacities: depth of understanding, mental quickness.
Information, often secret, about an enemy or about hostile activities.
A political or military department, agency or unit designed to gather information, usually secret, about the enemy or about hostile activities.
An entity that has such capacities.