一円[ichien] one yen
一円玉[ichiendama] one-yen coin
一円札[ichiensatsu] one-yen bill
円か[madoka] round
円やか[maroyaka] round

円グラフ[engurafu] pie graph
円安[enyasu] cheap yen
円為替[engawase] yen exchange
円域[eniki] yen bloc

丸柱[marubashira] column
火柱[hibashira] pillar of fire
蚊柱[kabashira] mosquito swarm
貝柱[kaibashira] adductor muscle
巻柱[makibashira] gold-covered woodwork at a temple in Hiraizumi

魂柱[konchuu] sound post (violin, etc.)
支柱[shichuu] prop
斜角柱[shakakuchuu] oblique prism
人柱[hitobashira] human pillar
水銀柱[suiginchuu] column of mercury