Careful

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Old English carful (see care, -ful).

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From Middle English careful, from Old English carful; equivalent to care +‎ -ful.

etymonline

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careful (adj.)

Old English cearful "mournful, sad," also "full of care or woe; anxious; full of concern" (for someone or something), thus "applying attention, painstaking, circumspect" (late Old English), the main modern sense; from care (n.) + -ful. In Middle English also "miserable, unfortunate," of persons or things; "causing fear, frightening, terrible." Careful-bed (early 14c.) was "sick-bed;" careful-day (c. 1200) was "judgment day."

Dragons dryfes doun

With kene carefull crie.

["The Wars of Alexander," c. 1400]