The symbolism of the cobweb is the association with spiders trapping prey and criminals being trapped behind bars. The spider web represents the prison (that's deep bro.) This tattoo is commonly found on the elbow because it also represents a lot of time with your elbows on the table. I.E. you've been sitting in prison doing nothing for so long that a spider is weaving a cobweb on your elbow. Convicts also often get the cobweb tattooed on their necks as well. If you see a multi-colored web, it's probably not a prison tat; prison tattoo artists rarely have access to colored ink.
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