ingress vs staircase

ingress

noun
  • A door or other means of entering. 

  • Permission to enter. 

  • The entrance of the Moon into the shadow of the Earth in eclipses, or the Sun's entrance into a sign, etc. 

  • The act of entering. 

verb
  • To manifest or cause to be manifested in the temporal world; to effect ingression 

  • To enter (a specified location or area) 

  • To intrude or insert oneself 

  • To enter into a zodiacal sign 

staircase

noun
  • A connected set of flights of stairs; a stairwell. 

  • A flight of stairs; a stairway. 

  • A set of locks (enclosed sections of waterway) mounted one above the next. 

verb
  • To modify (a signal, a graph, etc.) to reduce a smooth curve to a series of discrete steps. 

  • To increase one's share in a co-ownership. 

How often have the words ingress and staircase occurred in a corpus of books? (source: Google Ngram Viewer )