Dropworm

Drop´worm`

    (drǒp´wûrm`)
n.1.(Zool.) The larva of any geometrid moth, which drops from trees by means of a thread of silk, as the cankerworm or inchworm. See inchworm and geometrid.
Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.