To become more bad, severe, or difficult; the past tense of 'worsen.'
From 'worse' (Old English 'wiersa,' comparative of 'bad'), plus '-en' (to make), plus '-ed' (past tense). The '-en' suffix is an ancient method of forming verbs.
Interestingly, we have 'better' and 'worsen,' but no common verb 'bettened'—instead we say 'improve' or 'get better,' showing how language fills gaps with different words rather than always following patterns!
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