work up in WordNet English dictionary

1. 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 
   
2. bolster or strengthen
   "We worked up courage"; "build up confidence"; "ramp up security in the airports"
   build up  work up  build  ramp up 
   
3. develop
   "we worked up an as of an appetite"
   work up  get up 
   
4. come up with
   "His colleagues worked out his interesting idea"; "We worked up an ad for our client"
   work out  work up 
   

work up in English Wiktionary