the spider has a sinister aspect that should not be overlooked. The round metallic spider of our dreamer probably has a similar meaning. It has obviously devoured a number of human beings already, or their souls
Jung interprets the dreamed spider as a symbol of psychic inflation and soul-devouring self-enclosure, warning that those who place the ego as highest authority risk being swallowed into the spider’s belly.
, Civilization in Transition, 1964thesis