まっ四角[masshikaku] square
一天四海[ittenshikai] the world
下四半期[shimoshihanki] last quarter (of the year)
弦楽四重奏曲[gengakushijuusoukyoku] string quartet
再三再四[saisansaishi] repeatedly

三寒四温[sankanshion] alternation of three cold and four warm days
四つ[yottsu] four
四つんばい[yotsunbai] (crawl) on all fours
四つ角[yotsukado] four corners
四つ足[yotsuashi] four-footed (animal)

１月[ichigatsu] January
ひと月[ichigetsu] one month
下弦の月[kagennotsuki] waning moon
何ヶ月[nankagetsu] how many months?
何月[nangatsu] what month

佳月[kagetsu] good month
か月[kagetsu] (number of) months
花鳥風月[kachoufuugetsu] beauties of nature
各月[kakugetsu] every month
隔月[kakugetsu] every second month

くる病[kurubyou] rickets
アルツハイマー病[arutsuhaimaabyou] Alzheimer's disease
ケーソン病[keesonbyou] caisson disease
ハンセン病[hansenbyou] Hansen's disease
マレック病[marekkubyou] Marek's disease

悪病[akubyou] bad health
胃病[ibyou] stomach trouble
遺伝病[idenbyou] hereditary (genetic) disease
いもち病[tounetsubyou] rice blight
疫病神[yakubyougami] jinx (lit: god of pestilence)