transition
     n 1: the act of passing from one state or place to the next [syn:
           {passage}]
     2: an event that results in a transformation [syn: {conversion},
         {changeover}]
     3: a change from one place or state or subject or stage to
        another
     4: a musical passage moving from one key to another [syn: {modulation}]
     5: a passage that connects a topic to one that follows
Source: WordNet® 2.0