[; ]an increase in the amount of sth over a period of time 逐步的增长◆a worrying build-up of household debt 家庭债务的逐渐增加令人担忧◆a build-up in stocks of crude oil 原油库存的逐渐增加➡build sth up at build verb
[, ]the time before an important event, when people are preparing for it （重大事件的）准备期，准备过程◆the build-up to the conference 会议前的准备工作