妙法蓮華經玄贊 9.329

9.329

釋名者，「涌」謂上昇，「出」謂顯現，從地上昇而顯現，名從地涌出品。《玉篇》「涌，騰也」。涌如水上騰，故應作「涌」。「踴」跣也，非騰義。

Regarding the explanation of the title: "welling" (yong 涌) means ascending; "emergence" (chu 出) means appearing. Ascending from the earth and appearing is called "welling and emerging from the earth." The Yupian states: "Yong means to soar." Welling is like water surging upward, so it should be written as 涌. The character 踴 means leaping, not the sense of soaring.