iron man

noun3

1. •
   (figurative) Someone who performs a very complex, complicated, or strenuous task without assistance.

   • You don't have to be an iron man and do all the work yourself: there are people here who can help you.
2. •
   [usually plural] (slang, old-fashioned) A dollar.

   • This time it was thirty-five grand, a whole damn marching battalion of iron men, […] — 1993
3. •
   A self-acting spinning mule used in cotton manufacture.