Dearly

wiktionary

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From Middle English derely, deorliche, from Old English dēorlīċe(“worthily, richly”), equivalent to dear +‎ -ly.

etymonline

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dearly (adv.)

Old English deorlice "worthily, excellently;" see dear + -ly (2). From c. 1200 as "with tender affection;" from late 15c. as "at a high price."