Definitions
1.nounCapacity of mind, especially to understand principles, truths, facts or meanings, acquire knowledge, and apply it to practice; the ability to comprehend and learn.
2.nounAn entity that has such capacities.
3.nounInformation, usually secret, about the enemy or about hostile activities.
4.nounA political or military department, agency or unit designed to gather information, usually secret, about the enemy or about hostile activities.
5.nounAcquaintance; intercourse; familiarity.