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up to the individual

ADJECTIVE

optional

Synonyms

WEAK

alternative arbitrary discretional discretionary elective extra facultative free no strings attached noncompulsory nonobligatory not required open unforced unrestricted volitional voluntary

Antonyms

WEAK

compulsory forced required

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.