Bot. [f. Gr. κολεός sheath + ῥίζα root.] The sheath enveloping the radicle or rudimentary root in the embryo of grasses and other phanerogams; the root-sheath.
1866. in Treas. Bot.
1880. Gray, Struct. Bot., ii. 26. The radicle is completely enclosed by … a peculiar sheath … named the Coleorhiza.
1882. Vines, Sachs’ Bot., 638. In Ranunculus Ficaria, a tuberous lateral root is produced below the primary axis of the embryo, sheathed by a coleorhiza.
