The verb occur has 3 senses (first 3 from tagged texts)
1. (98) happen, hap, go on, pass off, occur, pass, fall out, come about, take place -- (come to pass; "What is happening?"; "The meeting took place off without an incidence"; "Nothing occurred that seemed important")
2. (21) occur, come -- (come to one's mind; suggest itself; "It occurred to me that we should hire another secretary"; "A great idea then came to her")
3. (9) occur -- (to be found to exist; "sexism occurs in many workplaces"; "precious stones occur in a large area in Brazil")