ANT: Disjunction, separation, severance, divorce, disagreement, discord, disharmony, secession, disruption, multiplication, diversification, division.

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KEY: Unique.

SYN: Sole, matchless, singular, rare, choice, uncommon, [See COMMON].

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KEY: Unison.

SYN: harmony, agreement, concord, union.

ANT: Discord, disharmony, disagreement, disunion, variance.

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KEY: Unit.