Meaning of work up

(verb) form or accumulate steadily; "Resistance to the manager's plan built up quickly"; "Pressure is building up at the Indian-Pakistani border"

develop; "we worked up an as of an appetite"

bolster or strengthen; "We worked up courage"; "build up confidence"; "ramp up security in the airports"

come up with; "His colleagues worked out his interesting idea"; "We worked up an ad for our client"