prescriptive

Meanings

1. 1
   adj

   pertaining to giving directives or rules

   prescriptive grammar is concerned with norms of or rules for correct usage

2. 2
   adj

   Of or pertaining to prescribing or enjoining, especially an action or behavior based on a norm or standard.

   For one thing, spoken language tends to be less subjected to prescriptive pressures than written language, and hence is a less artificial medium of com- munication (written language is often a kind of 'censored' version of spoken language). [...]

Etymology

From Latin praescriptivus (“relating to a legal exception”), from praescript- (“directed in writing”), from the verb praescribere.