Adjective rigorous has 3 senses
- rigorous, strict - rigidly accurate; allowing no deviation from a standard; "rigorous application of the law"; "a strict vegetarian"
Antonym: inexact (indirect, via exact)
- rigorous, stringent, tight - demanding strict attention to rules and procedures; "rigorous discipline"; "tight security"; "stringent safety measures"
Antonym: undemanding (indirect, via demanding)
- brutal, cruel, harsh, rigorous, unkind - used of circumstances (especially weather) that cause suffering; "brutal weather"; "northern winters can be cruel"; "a cruel world"; "a harsh climate"; "a rigorous climate"; "unkind winters"
Antonym: soft (indirect, via hard)
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