Definition of stem-winder in US English:
 stem-winder
(also stemwinder)
nounˈstemˌwīndərˈstɛmˌwaɪndər
US 1informal An entertaining and rousing speech.
 the speech was a classic stem-winder in the best southern tradition
 Example sentencesExamples
-  His was no Gettysburg Address, to be sure, but compared to some of the stem-winders of history, Mr. Clinton's speech, delivered at a rapid pace, flew by.
 -  Some news, like Democrat Barack Obama's dazzling stem-winder last July, took place when the networks were airing sitcom repeats or reality shows.
 -  Giuliani used some of the most overt forms in order to present a classic political stem-winder.
 -  How about Rush Limbaugh hanging out while John Kerry delivers his stem-winder?
 -  To say it wasn't a stem-winder is simply to say that it wasn't like Barack Obama's speech a few nights back, or Clinton's, or even Clark's or Sharpton's for that matter.
 
2dated A watch wound by turning a knob on the end of a stem.
Origin
  
Stem-winder (sense 1) from the notion of ‘winding up’ or causing a lively reaction from those listening.