PsychologyJuly 15, 2026

vacillation

/ˌvæsɪˈleɪʃən/

Definition

The act of swaying back and forth or shifting unsteadily between two extremes, specifically referring to the dramatic swings in mood found in bipolar spectrum disorders.

Etymology

Derived from the Latin 'vacillare,' meaning 'to sway' or 'to waver.' It entered English in the 16th century to describe physical unsteadiness, eventually evolving to encompass metaphorical indecision or emotional instability.

In the news

In the article, the term describes the intense and unstable shifts between manic highs and depressive lows that characterize bipolar spectrum disorders. It highlights how these erratic mood swings are a core component of the conditions being studied.

Linking bipolar disorder vulnerability to cannabis habits in college

Read the full article ↗

PsyPost

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