#1 occur v. [happen, hap, go on, pass off, 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". wn
#2 occur v. [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". wn
#3 occur v. to be found to exist; "sexism occurs in many workplaces"; "precious stones occur in a large area in Brazil". wn
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