Rise To The Occasion Meaning

(idiomatic, euphemistic, humorous) To achieve erection for sexual intercourse.

Example: 1874, Thomas Hardy, Far from the Madding Crowd, ch. 15:
  Gabriel, though one of the quietest and most gentle men on earth, rose to the occasion, with martial promptness and vigour. "That's my fist. . . . Now — the first man in the parish that I hear prophesying bad of our mistress, why" (here the fist was raised and let fall as Thor might have done with his hammer in assaying it) — "he'll smell and taste that."
1902, Arthur Conan Doyle, The Great Boer War, ch. 38:
  As it happened, this particular ordeal was exceedingly severe, but nothing can excuse the absolute failure of the troops concerned to rise to the occasion.
2011 Jan. 10, David Von Drehle, "The Real Lesson of the Tucson Tragedy," Time (retrieved 9 May 2015):
  How many times have we heard this story? The one about people rising to the occasion, storming the cockpit of the hijacked jet, racing into the burning building, tackling the gunman, saving a life.
2001, John R. Williams, The Life of Goethe: A Critical Biography:
  To his comic fury and shame, the traveller's 'master part' fails to rise to the occasion, and the girl's innocence is preserved.