ちょっと一杯[chottoippai] let's have a quick drink
ばつ一[batsuichi] being once divorced
一向[hitaburu] nothing but
サラダ一皿[saradahitosara] plate of salad

安全第一[anzendaiichi] safety first
一か八か[ichikabachika] sink or swim
一っ走り[hitoppashiri] spin (as in 'take a car for a spin')
一つ一つ[hitotsuhitotsu] one-by-one

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)

天魚[amago] land-locked variety of red-spotted masu trout (Oncorhynchus masou ishikawae)
御天気[otenki] weather
コール天[kooruten] corded velveteen
破天連[pateren] Portuguese Jesuits (in Japan in the 16th century)
天鵝絨[tengajuu] velvet

悪天[akuten] bad weather
悪天候[akutenkou] bad weather
悪天使[akutenshi] evil angels
旭日昇天[kyokujitsushouten] full of vigor and vitality (like the rising sun) (vigour)
一天[itten] the whole sky

海鷂魚[ei] ray (fish)
井の中の蛙大海を知らず[inonakanokawazutaikaiwoshirazu] parochial
一天四海[ittenshikai] the world
雲海[unkai] sea of clouds
沿海[enkai] coast

遠海[enkai] deep sea
黄海[koukai] Yellow Sea
温海[atsumi] warm sea
海の幸[uminosachi] seafood