aMalvaceous(Bot) Pertaining to, or resembling, a natural family of plants (Malvaceæ), of which the mallow is the type. The cotton plant, hollyhock, and abutilon are of this family. It was formerly classified as an order, and included the baobab and the silk-cotton trees. The baobab and silk-cotton trees are now placed in the family Bombacaceae, which is included with the Malvaceae in the order Malvales.
Century Dictionary and Cyclopedia
malvaceousPertaining or belonging to the order Malvaceæ, or mallow family.
Chambers's Twentieth Century Dictionary
adjMalvaceousmal-vā′shus (bot.) pertaining to plants of the mallow family.
Webster's Revised Unabridged Dictionary
L. malvaceus, from malva, mallows. See Mallow
No doubt the fungus is nursed by malvaceous weeds.
"The Culture of Vegetables and Flowers From Seeds and Roots, 16th Edition" by Sutton and Sons