build up in WordNet English dictionary

1. prepare oneself for a military confrontation
   "The U.S. is girding for a conflict in the Middle East"; "troops are building up on the Iraqi border"
   arm  build up  fortify  gird 
   
2. form or accumulate steadily
   "Resistance to the manager's plan built up quickly"; "Pressure is building up at the Indian-Pakistani border"
   build up  work up  build  progress 
   
3. bolster or strengthen
   "We worked up courage"; "build up confidence"; "ramp up security in the airports"
   build up  work up  build  ramp up 
   
4. enlarge, develop, or increase by degrees or in stages
   "build up your savings"
   build up 
   
5. change the use of and make available or usable
   "develop land"; "The country developed its natural resources"; "The remote areas of the country were gradually built up"
   build up  develop 
   

build up in English Wiktionary