The process of becoming accustomed or habituated to something through repeated exposure or practice.
From Latin 'assuefacere' (to accustom), combining 'ad-' (to) and 'suescere' (to become accustomed). The suffix '-faction' comes from 'facere' (to make), so the word literally means 'making accustomed.' It evolved in English to describe the gradual process of habit formation.
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