under one's own steam

under (one's) own steam

On one's own; with no assistance from anyone else. The injured player was fortunately able to walk off the field under his own steam. Look, Mom, I can finish this book report under my own steam, OK? I don't need you hovering over me correcting my spelling!
See also: own, steam
Farlex Dictionary of Idioms.

under one's own steam

Independently, without help, as in For two years I published the quarterly newsletter under my own steam. This expression uses steam in the sense of "driving power," as in a steam engine. [Early 1900s]
See also: own, steam
The American Heritage® Dictionary of Idioms by Christine Ammer.
See also:
  • at will
  • on one's own account
  • chew (one's) own tobacco
  • chew own tobacco
  • noggin
  • of (one's) own accord
  • of one's own accord
  • of own accord
  • of your own accord
  • do something in your own sweet time/way