• Webster's Revised Unabridged Dictionary
    • n Palmerworm (Zoöl) Any hairy caterpillar which appears in great numbers, devouring herbage, and wandering about like a palmer. The name is applied also to other voracious insects.
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Century Dictionary and Cyclopedia
    • n palmerworm A caterpillar; especially, a hairy caterpillar injurious to vegetation, but what kind is unknown or undetermined. The name occurs three times in the Bible (Joel i. 4; ii. 25; Amos iv. 9) as the translation of the Hebrew gāzām, rendered in the Septuagint κάμπη and in the Vulgate eruca. Some have supposed it to be a destructive kind of locust, as Pachytylus migratorius; but in Joel the name is expressly distinguished form “locust.” The Hebrew name is referred to a root meaning ‘to cut off’; the Greek κάμπη refers to the bending or looping of some caterpillars, apparently pointing to a looper or measuring-worm—that is, the larva of some geometrid moth; and the Latin eruca may have the same significance. The destructiveness of many of these geometrids would fully bear out the Biblical implication. See oubit.
    • n palmerworm In the United States, the larva of the tineid moth Ypsilophus pometella, which in eastern parts of the country appears on the leaves of the apple in June, draws them together, and skeletonizes them.
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