ˈbuild-up BrE AmE noun [countable usually singular]
1 . an increase over a period of time
build-up of
a heavy build-up of traffic on the motorway
2 . a description of someone or something before an event, in which you say they are very special or important:
The presenter gave her a big build-up.
3 . the length of time spent preparing an event:
I was running 20 miles a week in my build-up for the race.
⇨ build up at ↑ build 1