If you look into a microscope cancerous tumors spreading looks a lot like a crab with legs or resembles a spider, an octopus. In Greek the word carcinos means 🦀 thusly named by the Father of Medicine, Hippocrates.
Astrology/Zodiac signs are just entertainment. The disease of cancer can be deadly to all individuals born from Jan to Dec. Just so you know Humans are not Crabs.
Go out into an area that gets totally dark and you can see stars. Have some fun on a warm summer night laying on the ground with Becky, John, Ali and Ying..now, what images ,shapes do you see ? Don’t use the same ones as before like a bull or lion..use your imagination. That’s what the ancients did. It’s not literally those images. They are clusters of stars, dust and rocks.
Don’t let astrology dumb you down