rigorous rigorous /ˈrɪgɝəs/

adjective

1. () Demanding strict attention to rules and procedures  ( stringent , tight , rigorous )
   demanding strict attention to rules and procedures
    Rigorous discipline
   rigorous discipline
    Tight security
   tight security
    Stringent safety measures
   stringent safety measures
   
2. () Rigidly accurate; allowing no deviation from a standard  ( rigorous , strict )
   rigidly accurate; allowing no deviation from a standard
    Rigorous application of the law
   rigorous application of the law
    A strict vegetarian
   a strict vegetarian