#simultaneity__simultaneousness  happening or existing or done at the same time
  supertype:  timing  the time when something happens
  subtype:  co-occurrence__concurrence__conjunction  the temporal property of two things happening at the same time; "the interval determining the coincidence gate is adjustable"
     subtype:  concomitance  occurrence or existence together or in connection with one another
     subtype:  overlap  the property of partial coincidence in time
     subtype:  contemporaneity__contemporaneousness__contemporaneousnes  the quality of belonging to the same period of time
     subtype:  unison.co-occurrence  occurring together or simultaneously: "the two spoke in unison"

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