The wormlike larvae of butterflies and moths. The term appears in different English versions to translate various Hebrew words, NIV not referring to caterpillars at all.
Chasil refers to a particular stage of the grasshopper or locust. Apparently in this stage wings have begun to develop but are not folded together. They could cause famine in a land, eating all the crops (1 Kings 8:37;
Joel 1:14). They symbolized gathering booty or spoil of battle (Isaiah 33:4). They made their mark on Israelite history in the plagues in Egypt (Psalms 46:1).
Yeleq is the first stage after emerging from the egg. The flying apparatus has begun to develop but is invisible. The word could be used to describe the plague on Egypt (Psalms 105:34). They were noted for covering or filling up an area (Jeremiah 51:14). They swarmed over a land as an army in formation marched into a country (Jeremiah 51:27;
Joel 2:25). They multiplied quickly and ate up all in front of them before flying away to attack another land (Nahum 3:15-16). Obviously such language is not fully appropriate for the first stage of the animal, showing that the various terms became synonyms and could be used interchangeably to describe typical activities of the grasshopper or locust.
Gazam is traditionally defined as the just matured grasshopper ready for flight. Other scholars would identify it as the true caterpillar. Its name comes from a Hebrew root word meaning, “to cut off,” thus describing the animal's destructive ability to bite through weeds, grain, fig leaves, grapes, olive trees, fruit, and even small twigs and branches. Compare
Joel 2:25. This stage is variously translated as “palmerworm” (KJV), “gnawing locust” or “caterpillar” (NAS), “locust” (NIV), “cutting locust” (NRSV).
‘Arbeh is the mature, swarming locust—schistocera gregaria—which grows to six centimeters in length. The Exodus plague narrative features them (Exodus 10:14-19). They were classified as hopping animals (Job 39:20) with jointed legs and so were clean for Israel to eat (Leviticus 11:20-23). Their devouring habits made them a part of God's threatened curses on a disobedient people (Deuteronomy 28:38). Their wandering and swarming resembled that of an army (Judges 6:5;
Nahum 3:17). They were harmless to the human body, since people could easily shake them off (Psalms 109:23).