Old English handful "as much as can be held in the open hand;" see hand (n.) + -ful. Also a linear measurement of four inches, a handbreadth (early 15c.). Meaning "a small portion or part" is from mid-15c. Figurative meaning "as much as one can manage" is from 1755; figurative expression have (one's) hands full "have enough to do" is from late 15c. Plural handfulls. Similar formation in German handvoll, Danish haanfuld.