The Collaborative International Dictionary
spanworm
spanworm \span"worm`\ (sp[a^]n"w[^u]rm`), n. (Zo["o]l.) The larva of any geometrid moth, as the cankerworm; a geometer; a measuring worm.
Wiktionary
spanworm
n. A measuring worm.
Usage examples of "spanworm".
They drag-crawled and with their wavering spanworm walk stomped toward the train and even touched it and gnawed at it, marked it with stone-hard teeth and caustic spit.