"unable to act for oneself," c. 1200, from help (n.) + -less. Related: Helplessly; helplessness. In Middle English and later sometimes also "unable to give help, affording no help" (late 14c.), but this was never common.
1. Children are dying, and I am helpless to do anything.
2. Oh, to think of his poor wife, standing there helpless.
3. They are not merely helpless victims.
4. the helpless victims of war
5. The other team was helpless and we had a real field day.