fortification

noun

1. 1

   The act of fortifying; the art or science of fortifying places to strengthen defence against an enemy.

2. 2

   That which fortifies; especially, a work or works erected to defend a place against attack; a fortified place; a fortress; a fort; a castle.

3. 3

   An increase in effectiveness, as by adding ingredients.

4. 4

   A jagged pattern sometimes seen during an attack of migraine.