use-ful / yo͞os-fəl
1. helpful, serviceable
Unless what we do is useful, glory is vain.
2. providing for a common need; having a practical purpose; utilitarian
The production of too many useful things results in too many useless people.
Karl Marx, 1818 – 1883
useful, a combination of the English adjectival sufix “-ful” (full of, characterized by) and the English noun “use,” which comes from the Latin noun usus (use) [derived from the Latin verb utor, uti, usus (use)] through the Old French noun us, use.
Thank you to Allen Ward for providing this etymology.