Painful

wiktionary

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From Middle English paynful, peinful, peynful, paynefull, peynefull, equivalent to pain +‎ -ful. Compare Danish pinefuld(“painful”).

etymonline

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painful (adj.)

mid-14c., peineful, "characterized by or attended by pain" (originally of the Crucifixion), from pain (n.) + -ful. Meaning "causing physical pain" is from c. 1400; that of "inflicting pain" (of punishments, etc.) is by mid-15c. Related: Painfully; painfulness.