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

ダムダム弾[damudamudan] dum-dum ammunition
弾機[hatsujou] spring (e.g. coil, leaf)
パイプ爆弾[paipubakudan] pipe bomb
プラスチック爆弾[purasuchikkubakudan] plastic explosive
曳火弾[eikadan] tracer bullet

曳光弾[eikoudan] tracer bullet
円弾[endan] round shot
煙弾[endan] smoke bomb
核弾頭[kakudantou] nuclear warhead
核爆弾[kakubakudan] nuclear weapon