What is the meaning of occur?

verb

• Come to pass.
  • usage: "What is happening"; "The meeting took place off without an incidence"; "Nothing occurred that seemed important"
  • synonyms: happen, hap, go on, pass off, pass, fall out, come about, take place
• Come to one's mind; suggest itself.
  • usage: "It occurred to me that we should hire another secretary"; "A great idea then came to her"
  • synonyms: come
• To be found to exist.
  • usage: "sexism occurs in many workplaces"; "precious stones occur in a large area in Brazil"