carefulcareful

Careful comes from Middle English careful ‘sorrowful, anxious’, from Old English carful ‘anxious’, from caru ‘care, worry’ + -ful.

1. Proto-Germanicc. 500 BCE–200 CE*karō¹reconstructed
2. Proto-West Germanicc. 200–500 CE*karu¹‘care’reconstructed
3. Old Englishc. 450–1150caru²‘worry’
4. Old Englishc. 450–1150carful³‘anxious’
5. Middle Englishc. 1150–1500careful³‘sorrowful’
6. Englishearliest quotation 1590careful³

1. ¹ Wiktionary, Old English caru
2. ² Wiktionary, Old English carful
3. ³ Wiktionary, English careful
4. Earliest quotation in Wiktionary’s entry: 1590, Edmund Spenser, Book III, Canto I: “Where through long watch, and late daies weary toile,…”.