WordNet (r) 3.0 (2006):

angst
    n 1: an acute but unspecific feeling of anxiety; usually
         reserved for philosophical anxiety about the world or about
         personal freedom

Moby Thesaurus II by Grady Ward, 1.0:

77 Moby Thesaurus words for "angst":
   agitation, all-overs, anguish, anxiety, anxiety hysteria,
   anxiety neurosis, anxious bench, anxious concern, anxious seat,
   anxiousness, apprehension, apprehensiveness, boredom,
   cankerworm of care, care, cheerlessness, concern, concernment,
   discomfort, discomposure, discontent, dislike, displeasure,
   disquiet, disquietude, dissatisfaction, distress, disturbance,
   dread, dullness, emptiness, ennui, existential woe, fear, flatness,
   foreboding, forebodingness, grimness, inquietude, joylessness,
   lack of pleasure, malaise, misgiving, nausea, nervous strain,
   nervous tension, nervousness, nongratification, nonsatisfaction,
   overanxiety, painfulness, perturbation, pins and needles, pucker,
   savorlessness, solicitude, spleen, staleness, stew, strain,
   suspense, tastelessness, tediousness, tedium, tension, trouble,
   uncomfortableness, unease, uneasiness, unhappiness, unpleasure,
   unquietness, unsatisfaction, upset, vexation, vexation of spirit,
   zeal