Easton's Bible Dictionary: M. G. Easton, M.A., D.D.

Worm

1. Heb.sas (Isa. 51:8), denotes the caterpillar of the clothes-moth.
2. The manna bred worms (tola'im), but on the Sabbath there was not any worm (rimmah) therein (Ex. 16:20, 24). Here these words refer to caterpillars or larvae, which feed on corrupting matter.

These two Hebrew words appear to be interchangeable (Job 25:6; Isa. 14:11). Tola'im in some places denotes the caterpillar (Dt. 28:39; Jonah 4:7), and rimmah, the larvae, as bred from putridity (Job 17:14, 21:26, 24:20). In Mic. 7:17, where it is said, "They shall move out of their holes like worms," perhaps serpents or "creeping things," or as in the Revised Version, "crawling things," are meant.

The word is used figuratively in Job 25:6; Ps. 22:6; Isa. 41:14; Mk. 9:44, 46, 48; Isa. 66:24.