pre‧scrip‧tive /prɪˈskrɪptɪv/ adjective

1. saying how something should or must be done, or what should be done:
prescriptive teaching methods

2. stating how a language should be used, rather than describing how it is used Antonym : descriptive:
prescriptive grammar

3. prescriptive right British English law a right that has existed for so long that it is as effective as a law
—prescriptively adverb

[TahlilGaran] Dictionary of Contemporary English ▲