To give capacity to; to make capable of holding, containing, or performing something.
From capacity plus -fy, a Latin suffix meaning 'to make.' The word is quite rare and technical, appearing occasionally in specialized or archaic texts.
Capacify is so obscure that most modern writers would use 'enable' or 'give capacity to' instead—but it's a grammatically perfect construction that shows how English can theoretically create new verbs from nouns using the -fy suffix.
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