A tangle is a jumble. You might have a tangle of cords behind your computer or a tangle of complications related to your taxes. Whatever it is, once something is in a tangle, it's difficult to sort out.
The word tangle likely originated from a Scandinavian source — taggla, in a Swedish dialect, means “disarrange.” Tangle also can be used as a verb: you may tangle your hair as a fashion statement, but then it hurts to comb it out. As a noun, tangle can refer to an argument or a fight between two people: if you're really feisty, people might be warned away from getting into a tangle with you.