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Definitions

vacillation

[vas-uh-ley-shuhn] / ˌvæs əˈleɪ ʃən /
NOUN
irresolution
Synonyms
STRONGEST
hesitation
STRONG
doubt hesitancy inconstancy indecision indecisiveness irresoluteness uncertainty
WEAK
tentativeness
Antonyms
STRONG
certainty
NOUN
fluctuation
Synonyms
STRONG
sway swing vibration wave
WEAK
swaying

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