be afraid, serpent, worm

Boyd’s Bible Dictionary:

Many Hebrew words are translated worm, all indicative of something loathsome, destructive, helpless, or insignificant, as the moth
(Isa. 51:8); maggot (Job 19:26); possibly the serpent (Mic. 7:17). The allusion (Isa. 64:24; {vi 24583-24587}Mark 9:44-48), is thought to be to the valley near Jerusalem where the refuse of the city constantly bred worms and where fires were kept burning to consume the collections. The helplessness of the worm affords the figures (Job 25:6; Psa. 22:6; Isa. 41:14).

Concise Bible Dictionary:

The worm is used symbolically to show the extreme feebleness of man (Job 17:14; Job 25:6). In blessing Israel Jehovah said, “Fear not, thou worm Jacob” (Isa. 41:14); and the Lord, to indicate the low estate in which He was, said, “I am a worm and no man” (Psa. 22:6). In the grave man’s body becomes the companion of worms, if they do not actually feed upon it (Job 21:26; Job 24:20; Isa. 14:11). Of the eternal punishment of the wicked it is recorded “their worm dieth not” ({vi 24583;24585;24587}Mark 9:44,46,48: Compare Isa. 66:24). Herod Agrippa, being smitten by an angel, was literally “eaten of worms” (Acts 12:23). In Job 25:6 man is compared to a worm—literally “a maggot”—an apt figure of moral corruption.
Maggots

Strong’s Dictionary of Hebrew Words:

Number:
2119 (find all occurrences in KJV Bible)
Transliteration:
zachal
Phonic:
zaw-khal’
Meaning:
a primitive root; to crawl; by implication, to fear
KJV Usage:
be afraid, serpent, worm