[かくけい;かっけい, kakukei ; kakkei] (n) (1) (N)-cornered polygon, incl. triangle; (2) (esp. かくけい) Japanese rectangular envelope (opening on the short dimension; numbered 0-8, A3, A4, each with different sizes)#18775
[リンさんカルシウム(リン酸カルシウム);りんさんカルシウム(燐酸カルシウム), rin san karushiumu ( rin san karushiumu ); rinsan karushiumu ( rin san karushiumu )] (n) calcium phosphate (Ca3(PO4)2)