#rigidifying__rigidification  the process of becoming stiff or rigid
  supertype:  natural_process__naturalproces__natural_action__naturalaction__action__activity  a process existing in or produced by nature (rather than by the intent of human beings); "the action of natural forces"; "volcanic activity"
  subtype:  rigor_mortis  muscular stiffening that begins 2 to 4 hours after death and last for about 4 days

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