Mechoacan \Me*cho"a*can\, n. A species of jalap, of very feeble properties, said to be obtained from the root of a species of Convolvulus (C. Mechoacan); -- so called from Michoacan, in Mexico, whence it is obtained.

Source: Webster's Revised Unabridged Dictionary (1913)
 

Convolvulus \Con*vol"vu*lus\, n.; pl. L.Convolvuli, E. Convoluluses. [L., bindweed, fr. convolvere to roll around. So named from its twining stems.]

(Bot.) A large genus of plants having monopetalous flowers, including the common bindweed (C. arwensis), and formerly the morning-glory, but this is now transferred to the genus Ipom[ae]a.

The luster of the long convolvuluses That coiled around the stately stems. --Tennyson.

Source: Webster's Revised Unabridged Dictionary (1913)