What does the word onset mean?

Usage examples for onset

  1. And now, whereas he had given her the right to warn him against taking too much wine, he was fain to call her his little watchman, by reason that it is the watchman's part to give warning of the enemy's onset. – The Complete Historical Romances of Georg Ebers by Georg Ebers
  2. With a trick of his horse, the wild man escaped the sudden onset, although it must have amazed him sadly that any durst resist him. – Lorna Doone, A Romance of Exmoor by R. D. Blackmore