The Lombard rhythm or Scotch snap is a syncopated musical rhythm in which a short, accented note is followed by a longer one. This reverses the pattern normally associated with dotted notes or notes inégales, in which the longer value precedes the shorter.
In Baroque music, a typical Lombard rhythm consists of a stressed sixteenth note, or semiquaver, followed by a dotted eighth note, or quaver.
In Scottish country dances, the Scotch snap (or Scots snap) is a prominent feature of the strathspey.
References
Lombard rhythm Wikipedia(Text) CC BY-SA