flagpole vs keep out

flagpole

verb
  • Exit a country momentarily and reenter. Usually this is done to satisfy immigration requirements. 

noun
  • A tall pole up which one or more flags may be raised and flown. 

keep out

verb
  • To refrain from entering a place or condition. 

  • To restrain someone or something from entering a place or condition. 

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