Synonyms: aware, cognizant, conscious, sensible, awake
These adjectives mean having knowledge or discernment of something. Aware implies knowledge gained through one's own perceptions or by means of outside information: became aware of a cooling in their relationship; was not aware that the legislation passed.
Cognizant is a formal equivalent of aware: "Our research indicates that the nation's youth are cognizant of the law" (Jerry D. Jennings).
Conscious emphasizes the inner workings of the mind or the direct experience of the senses as opposed to knowledge gained through information: "Was Darwin really conscious of what he had done as he wrote his last professional lines?" (Stephen Jay Gould). "She was clearly conscious of the beauty of the night, its stars and sharp cold" (Oliver La Farge).
Sensible implies knowledge gained through intellectual perception: "I am sensible that the mention of such a circumstance may appear trifling" (Henry Hallam).
To be awake is to be fully alert to something: "He was as much awake to the novelty of attention in that quarter as Elizabeth herself could be" (Jane Austen).