abstention

n. act of abstaining, act of refraining, self denial; act of refraining from voting

Abstention is a term in election procedure for when a participant in a vote either does not go to vote (on election day) or, in parliamentary procedure, is present during the vote, but does not cast a ballot. Abstention must be contrasted with "blank vote", in which a participant in a vote cast a deliberately unlegitimate vote (drawing pictures on the ballot, etc.) or in which he simply casts a blank vote: a "blank (or white) voter" has voted, although his vote may be considered a spoilt vote, depending on each legislation, while an abstentionnist hasn't voted. Both forms (abstention and blank vote) may or may not, depending on the circumstances, be considered as protest vote.
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Noun
1. the trait of abstaining (especially from alcohol)
(synonym) abstinence
(hypernym) self-discipline, self-denial
(derivation) abstain, refrain, desist

n. abstention, abstain; forbearance, abstinence

(a.)
The act of abstaining; a holding aloof.