I'll take a whack at it.
Cold Crashing: Reducing the temperature of a finished beer for a relatively short amount of time, i.e. days, in order to get much of the suspended matter to drop out before packaging. Usually done in a primary fermenter.
Lagering = Cold Conditioning: Reducing the temperature of a finished beer for weeks or months, in order to get suspended matter to drop out and get a very clear beer, i.e. clearer than what can be obtained from just cold crashing . Usually done in a secondary vessel or serving keg. Technically, every beer that's stored cold for an extended period of time is being lagered.