for·ti·fy 
/ˈfoɚtəˌfaɪ/ verb
for·ti·fies; for·ti·fied; for·ti·fy·ing /ˈfoɚtəˌfaɪ/ verb [+ obj] 1 : to strengthen (a place) by building military defenses (such as walls, trenches, etc.)
▪ fortify a city against attack ▪ a heavily fortified town/border ▪ a city fortified by high walls 2 a : to make (someone or something) stronger
▪ fortify [=strengthen] the body against illness ▪ Support for his theories has been fortified by the results of these experiments.
b : to make (yourself) feel stronger or less fearful
▪ He took a deep breath to fortify himself before stepping onto the stage. 3 : to improve the usefulness or quality of (something) by adding something to it : enrich
▪ fortify soil with fertilizer ▪ milk fortified with vitamin D
▪ fortify a city against attack ▪ a heavily fortified town/border ▪ a city fortified by high walls
▪ fortify [=strengthen] the body against illness ▪ Support for his theories has been fortified by the results of these experiments.
b : to make (yourself) feel stronger or less fearful
▪ He took a deep breath to fortify himself before stepping onto the stage.
▪ fortify soil with fertilizer ▪ milk fortified with vitamin D
