Full of hostility, hatred, or destructive intent; inclined to reduce or diminish something.
From 'bate' (to reduce/diminish or to show hostility) plus the suffix '-ful' meaning 'full of.' The word combines the sense of aggression with reduction.
This is a wonderfully archaic word that captures the idea of 'hate-full'—bateful looks or actions were those filled with anger and malice, and it's rarely used today except in historical literature and poetry.
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