BuddHa

At least in the Westernized version of Buddhism I have heard, Buddha is not a deity.  He is a man who achieved enlightenment in the Hindu sense in one lifetime instead of in many reincarnations in a state of self-awareness.  He achieved this by living many different lifestyles including that of a decaying waterfowl.  After enlightenment, he recognized his unity with the universal oneness, or atman.  He thus got to stop being reincarnated, just like many other people who had achieved enlightenment over many lifetimes.  Since the original Buddha, several other Buddhists have accomplished this feat and are thus called Buddha as well (i.e. the fat LaughingBuddha of China).  If anything, the name for the sole deity in the universe is "atman".