A corrective wave according to Elliott Wave Principles that travel in an ABC sequence.
In the conventional Elliott Wave mode, impulse waves have 5-wave structures while corrective wave have 3-wave structures ie. ABC. A zig zag is a 3-wave correction that goes against the trend (as opposed to going sideways like a triangle or flat pattern.
Wave A in the zig zag can be broken down to 5-wave structure, and wave B is a 3-wave structure, finally ending with a wave C that also bears a 5-wave structure. This would complete a zig zag, and is either complete with the correction, or is a wave A in a more complex correction.