fortification has definitions from the field of military
1
[ noun ] (military) defensive structure consisting of walls or mounds built around a stronghold to strengthen it

Synonyms

munition

Used in print

(Gerald Green, The Heartless Light....)

They possessed no outer fortifications , no hard shells of confidence ; they had enough difficulty getting from day to day , let_alone having an awful crime thrust upon them .

2
[ noun ] the art or science of strengthening defenses

Related terms

art arm

3
[ noun ] (military) the addition of an ingredient for the purpose of enrichment (as the addition of alcohol to wine or the addition of vitamins to food)

Synonyms

strengthening

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