Full of charm; attractive, delightful, and appealing in a magical or enchanting way.
Charm + -ful (full of). This combination became productive in English, creating adjectives meaning 'full of' or 'characterized by' something.
While 'charming' is common, 'charmful' is quite rare—English speakers prefer different words for the same meaning, showing how we don't always use every grammatical possibility available to us!
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