Fortification
WordNet
noun
(1) The addition of an ingredient for the purpose of enrichment (as the addition of alcohol to wine or the addition of vitamins to food)
(2) Defensive structure consisting of walls or mounds built around a stronghold to strengthen it
(3) The art or science of strengthening defenses
WiktionaryText
Noun
- The act of fortifying; the art or science of fortifying places in order to defend them against an enemy.
- That which fortifies; especially, a work or works erected to defend a place against attack; a fortified place; a fortress; a fort; a castle.