根茎,根源,起源
Rootstock \Root"stock`\, n. (Bot.) A perennial underground stem, producing leafly s?ems or flower stems from year to year; a rhizome.
rootstock n 1: a horizontal plant stem with shoots above and roots below serving as a reproductive structure [syn: {rhizome}, {rootstalk}] 2: root or part of a root used for plant propagation; especially that part of a grafted plant that supplies the roots