fortify

Concise Oxford English Dictionary © 2008 Oxford University Press:
fortify /ˈfɔːtɪfʌɪ/

▶verb (fortifies, fortifying, fortified)

• 1 provide with defensive works as protection against attack.

• 2 invigorate or encourage.

• 3 (often as adj. fortified) add spirits to (wine) to make port, sherry, etc.

  ■ increase the nutritive value of (food) by adding vitamins.

– derivatives
fortifiable adjective,
fortifier noun.

– origin ME: from Fr. fortifier, from late L. fortificare, from L. fortis ‘strong’.