Synonyms of necessary in English:

necessary


See definition of necessary

adjective

1‘planning permission is necessary’

SYNONYMS
obligatory, requisite, required, compulsory, mandatory, imperative, demanded, needed, called for, needful
essential, indispensable, vital, of the essence, incumbent
de rigueur
ANTONYMS

unnecessary, non-essential, dispensable

2‘their fate was a necessary consequence of progress’

SYNONYMS
inevitable, unavoidable, certain, sure, inescapable, inexorable, ineluctable, fated, destined, predetermined, predestined, preordained
ANTONYMS

possible