build·up 
/ˈbɪldˌʌp/ noun
plural build·ups /ˈbɪldˌʌp/ noun 1 : an increase in something that occurs as time passes [count] ▪ the country's military buildup [=an increase in the size of its military] ▪ There is a big traffic buildup on the highway. — often + of ▪ He had a buildup of fluid in the lungs. ▪ a buildup of tension/pressure/stress [noncount] ▪ You should clean the mechanism regularly to prevent buildup of dirt. 2 : things that are said to cause people to feel excited about something (such as a future event) or someone (such as a performer) [noncount] ▪ After all the buildup [=hype, publicity], I expected the movie to be better than it actually was. [count] ▪ Both players were given big buildups before the game. 3 [noncount] : a series of things that lead to an important event or occurrence — + to ▪ There have been many news stories during the buildup to the peace talks. ▪ The story/movie/song has a great buildup to a terrific ending.
