“Edgy” has two meanings, at least in American English. 1. The older meaning (the one I grew up knowing) is the one explained by Rob. It means being in a state of mind in which you are easily startled or annoyed or angered. It can be related to nervousness, or maybe to just feeling overly-tired. Example: “I’m feeling a bit edgy today. Would you please turn that music down? It’s really bothering me.” “Be careful of him. He’s acting really edgy and I’m afraid he will hurt you if you provoke him.” 2. The newer meaning is the one explained by Timothy and Irene.

Baron, “Edgy” and “nervous” do not mean the same thing. “Nervous” is an adjective describing an emotion (“worried and anxious”), and if that emotion is typical for a person, it describes a part of their personality. “She has a nervous disposition” is an old-fashioned way of saying that someone has anxiety. “Edgy” is an adjective describing something that (and by extension, someone who) challenges conventional thinking, who acts “on the edge”, and that provokes a reaction from people. Art can be edgy; this is almost a requirement of modern art. But art cannot be “nervous”. A horse or a dog can be nervous; they can’t be edgy. A person can be both edgy and nervous — at least grammatically. But mostly being “edgy” is a deliberate, confident choice. It’s not usually how you describe a nervous person.

Edgy and nervous have similar meanings but are not quite the same. Being edgy is a type of being nervous that implies that the subject is being defensive and maybe likely to lash out in some way, possibly attacking or simply just running away. it's usually used when people talk about being nervous about a confrontation

“On edge” means the same thing as nervous. “Edgy” would be used to describe a person who is counter cultural. For example, I would describe someone as being edgy they had lot of tattoos and piercings. That being said, it’s not that commonly used, and someone who is edgy to me might not be edgy to you... it is subjective.