Keywords: theory, theoretical, theorise
Sign Definition
As a Noun
                                            1.  An idea or set of ideas that is intended to explain something. English = theory.
                                          
                                          
                                        
                                            2.  A set of ideas that relate to a particular subject. English = theory.
                                          
                                          
                                        As a Verb or Adjective
                                            1.  To be based on or concerning the ideas and abstract principles of a subject, rather than the practical aspects of it. English = (be) theoretical.
                                          
                                          
                                        
                                            2.  To develop ideas about something in order to explain it. English = theorise.