The antonyms for the word "build ups" are "demolition," "destruction," "breakdown," "disintegration," and "collapse." These words imply the opposite of building up, which is the process of constructing, assembling, and strengthening something. Demolition denotes the act of tearing down existing structures or buildings, while destruction means obliterating something completely. Breakdown suggests a fault or inability to function as intended or designed. Disintegration refers to falling apart or dissolving, while collapse means a sudden and violent failure of something. These antonyms highlight the negative consequences of not building up or maintaining structures or relationships, leading to their eventual decline or destruction.