[われまどりろん, waremadoriron] (n) broken windows theory; criminological theory stating that serious crime can be prevented by maintaining the good physical condition of an urban environment
[ししょくていり;よんしょくていり, shishokuteiri ; yonshokuteiri] (n) four-color theorem (colour) (theorem stating that any map can be colored such that no two adjacent segments have the same color, if only four colors are used)
[むなふだ;むねふだ, munafuda ; munefuda] (n) sign staked to a building's ridgepole at construction time stating the building's donor, builder, date, reason for construction, etc.