start on

verb3

1. •
   To begin using (something); to set about on a task; to be initiated to begin using.

   • We're starting on the long-delayed project soon.
   • They haven't started her on solid foods yet.
2. •
   (informal) To criticize.

   • Don't start on her about that again!
3. •
   (informal) To be instigated to talk about, rant or complain regarding a frequent topic.

   • Don't start me on that again.