The Collaborative International Dictionary of English v.0.48:

awareness \awareness\ n.
   conscious knowledge; as, he had no awareness of his mistakes.

   Syn: cognizance, knowingness.
        [WordNet 1.5]

   2. a state of elementary or undifferentiated consciousness;
      as, the crash intruded on his awareness.

   Syn: sentience.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

awareness
    n 1: having knowledge of; "he had no awareness of his mistakes";
         "his sudden consciousness of the problem he faced"; "their
         intelligence and general knowingness was impressive" [syn:
         awareness, consciousness, cognizance, cognisance,
         knowingness] [ant: incognizance]
    2: state of elementary or undifferentiated consciousness; "the
       crash intruded on his awareness" [syn: awareness,
       sentience]

Moby Thesaurus II by Grady Ward, 1.0:

50 Moby Thesaurus words for "awareness":
   advertence, advertency, alertness, apperception, appreciation,
   appreciativeness, assiduity, assiduousness, attention,
   attention span, attentiveness, care, cognition, cognizance,
   concentration, consciousness, consideration, diligence, ear,
   earnestness, experience, feeling, heed, heedfulness, insight,
   intentiveness, intentness, mindfulness, noesis, note, notice,
   observance, observation, percept, perception, realization,
   recognition, regard, regardfulness, remark, respect, response,
   response to stimuli, sensation, sense, sense impression,
   sense perception, sensibility, sensory experience, thought