Capable of being delighted; able to be pleased, charmed, or made happy with delight.
From delight (from Old French delite, from Latin delectare, to please) plus the adjective suffix -able, creating a word meaning 'capable of being delighted.'
The suffix -able usually attaches to verbs (like 'readable' from 'read'), but 'delightable' attaches to a noun to mean 'capable of receiving delight'—a less common pattern that shows how creative English speakers can be with word formation.
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