To make something less strong or powerful; to cause someone or something to lose strength, energy, or effectiveness.
From Old Norse veikr (weak, soft) via Old English wæc; related to 'week' in Romance languages because the moon's waning phase was called 'weak' by ancient peoples.
It's fascinating that in many European languages, 'weak' and 'week' are related—both refer to things that diminish or become smaller, connecting to the lunar cycle our ancestors watched so carefully.
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