Comparative form of 'bully': more aggressive, dominating, or inclined to bully others; or more muscular and bullish in appearance.
From 'bully' with the comparative suffix '-er', following the standard pattern for comparing adjectives. 'Bully' itself comes from Dutch 'boel' meaning 'lover' or 'brother,' which evolved to mean 'ruffian' in 17th century London.
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