The process of making something venomous or poisonous, or of filling something with bitterness and malice.
From 'envenom' plus suffix '-ization' (making or becoming). The '-ize' infix and '-ation' suffix together create a noun describing a process of transformation.
This is an extremely rare word—so rare that many dictionaries don't include it—which shows how English speakers prefer 'envenoming' or 'poisoning' over this longer technical form.
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