Both Uses of

fortify
in
Oryx and Crake

Some vicious Ebola or Marburg splice, one of the fortified hemorrhagics.†
p. 53.7 *

fortified = to make stronger

He watched the news some more, drinking Scotch to fortify himself, but spacing his intake.†
p. 327.7

Definition:

to make stronger

in various senses, including:

to add defensive fortifications to a site to withstand attack -- as in "fortify the camp"
to make a structure or organization stronger -- as in "fortify the wall"
to inspire emotional and mental strength -- as in "fortify her spirits"
to strengthen an argument -- as in "fortify our argument"
to add nutrients to increase the healthfulness -- as in "bread fortified with folic acid and iron"
to add alcohol to make a drink stronger and/or less prone to spoiling -- as in "port, sherry, madeira, and other fortified wines"