Open English Wordnet
Verbs
(v)build up, work up, build, progressform or accumulate steadily“Resistance to the manager's plan built up quickly”,
“Pressure is building up at the Indian-Pakistani border” (v)build up, work up, build, ramp upbolster or strengthen“We worked up courage”,
“build up confidence”,
“ramp up security in the airports” (v)work out, work upcome up with“His colleagues worked out his interesting idea”,
“We worked up an ad for our client”