- The larva of a small two-winged fly (Sciara), which marches in large companies, in regular order. See Cotton worm, under Cotton.
- A lepidopterous insect, which in the larval state often travels in great multitudes from field to field, destroying grass, grain, and other crops. The common army worm of the northern United States is Leucania unipuncta. The name is often applied to other related species, as the cotton worm.
Webster's Revised Unabridged Dictionary
| APA | Webster's. (2011). army worm. Retrieved September 24, 2026, from http://smartdefine.org/army_worm/definitions/1975890 |
| Chicago | Webster's. 2011. "army worm" http://smartdefine.org/army_worm/definitions/1975890 (accessed September 24, 2026). |
| Harvard | Webster's 2011, army worm, Smart Define, viewed 24 September, 2026, <http://smartdefine.org/army_worm/definitions/1975890>. |
| MLA | Webster's. "army worm" 27 May 2011. Web. 24 September 2026. <http://smartdefine.org/army_worm/definitions/1975890> |