[1] : The Collaborative International Dictionary of English v.0.48

occur \occur"\, v. i. imp.  p. p. occurred; p. pr.  vb. n.
   occurring. l. occurrere, occursum; ob see ob- +
   currere to run. see course.
   1. to meet; to clash. obs.
      1913 webster

            the resistance of the bodies they occur with.
                                                  --bentley.
      1913 webster

   2. to go in order to meet; to make reply. obs.
      1913 webster

            i must occur to one specious objection. --bentley.
      1913 webster

   3. to meet one's eye; to be found or met with; to present
      itself; to appear.
      1913 webster

            in scripture, though the word heir occur, yet there
            is no such thing as "heir" in our author's sense.
                                                  --locke.
      1913 webster

   4. to happen; to take place; as, i will write if opportunity
      occurs.
      1913 webster

   5. to come to the mind; to arise in the mind; to suggest
      itself; to be presented to the imagination or memory; --
      of an idea or thought; as, it never occurred to me to call
      john to ask.
      1913 webster +pjc

            there doth not occur to me any use of this
            experiment for profit.                --bacon.
      1913 webster
see also:
occurred occurring ob- course 

[2] : WordNet (r) 2.0

occur
     v 1: come to pass; "what is happening?"; "the meeting took place
          off without an incidence"; "nothing occurred that seemed
          important" syn: happen, hap, go on, pass off, pass,
           fall out, come about, take place
     2: come to one's mind; suggest itself; "it occurred to me that
        we should hire another secretary"; "a great idea then came
        to her" syn: come
     3: to be found to exist; "sexism occurs in many workplaces";
        "precious stones occur in a large area in brazil"
     also: occurring, occurred
see also:
happen hap go on pass off pass fall out 
come about take place come occurring occurred 

[3] : WordNet (r) 2.0

occurring
     see occur
see also:
occur 

Occurring >> O Words
Occurring, definition of term: Occurring
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