transition

noun

1.
the act of passing from one state or place to the next
timeflow passage
Derived from:
transit transition
2.
an event that results in a transformation
changeover conversion
Derived from:
transition
3.
a change from one place or state or subject or stage to another
frothering overgang overswitch switch-over upshift
Derived from:
transition
4.
a musical passage moving from one key to another
modulation
5.
a passage that connects a topic to one that follows