Recourse is a source of help. If you're failing trigonometry in spite of studying until your brain hurts, you may have no recourse but to hire a tutor.
Recourse comes from the Latin word recursus, meaning “to run back or retreat.” People seek recourse from such difficulties as debt, illness and legal woes, so you can think of recourse as the words "retreating from curses" squished together. For the record, though, the cursus in recursus means course, not curse. Actually, no one knows where the word curse comes from. There may be some connection between cursus and curses, but then again, there may not be.