Prerequisite

مترادف و متضاد prerequisite

1. adjective necessary
   Synonyms: called for, essential, expedient, imperative, important, indispensable, mandatory, necessitous, needful, obligatory, of the essence, required, requisite, vital
   Antonyms: optional, unnecessary, voluntary
2. noun condition, necessity
   Synonyms: essential, imperative, must, need, postulate, precondition, qualification, requirement, requisite, sine qua non
   Antonyms: extra, option