Are there different forms of the word anxiety?

worry, concern, apprehension, apprehensiveness, uneasiness, unease, fearfulness, fear, disquiet, disquietude, inquietude, perturbation, agitation, angst, misgiving, nervousness, nerves, tension, tenseness; informal heebie-jeebies, butterflies (in one's stomach), jitteriness, the jitters, twitchiness