Delightful

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Middle English: from Old French delitier (verb), delit (noun), from Latin delectare ‘to charm’, frequentative of delicere . The -gh- was added in the 16th century by association with light1.

wiktionary

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From Middle English deliteful, delitfull, equivalent to delight +‎ -ful.

etymonline

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delightful (adj.)

c. 1400, "joyous;" 1520s, "highly pleasing, affording great pleasure or satisfaction," from delight (n.) + -ful. Related: Delightfully; delightfulness.