Noun: a nervous disorder characterized by a state of excessive uneasiness and apprehension, typically with compulsive behavior or panic attacks.
It's a feeling of wanting to run away and hide in a dark place away from everyone and everything and to never come back out. Trying to have words come out but instead you're left with jumbling over your words and stuttering. Maybe even to the point where you can't even get any words or sounds out of your mouth. Intense feelings of sudden doom and hopelessness. Chest pains and feeling like you can't breathe. Just praying you won't pass out and will get through whatever current situation is happening. Standing there scratching at your skin to calm yourself and hoping no one notices. Refusing to do anything out of normal routine. Fearing meeting and talking to new people. Overthinking and picking apart everything. Always worrying and questioning everything. Wanting to constantly cry. Crying until you can't breathe anymore. Numbness and shaking throughout your whole body and spacing out. Heartbeat is so fast you think it might explode. Nausea and dizziness to the point where you can't stand anymore. Forever afraid of being judged and being super self conscious and insecure about yourself in everything you do. Hoping you don't screw things up. Hoping you can survive the day without having a full blown anxiety attack.
There's just not one word or one way to describe anxiety. It comes in all different forms and it's different for everyone. Above I described it as I see it and from my own personal experience and ongoing battle with it. Anxiety sucks. It's an every day battle. Take baby steps. You can ease your anxiety. Don't rush into any situation you aren't comfortable with. Always remember to take deep breathes and to tell yourself you can do it, don't let your mind win.