Here is the definition Q posted.
Definition of start (Entry 1 of 3)
intransitive verb
1a: to move suddenly and violently : SPRING
started angrily to his feet
b: to react with a sudden brief involuntary movement
started when a shot rang out
2a: to issue with sudden force
blood starting from the wound
b: to come into being, activity, or operation
when does the movie start
the rain started up again