Sewing patterns will commonly refer to fabrics as having either 1 way, 2 way or 4 way stretch. Some companies will have a different method but here at Super Cheap Fabrics, here is how we classify a 1, 2 or 4 way stretch.

The first thing to note is that all fabrics will have stretch either along the selevege or length of the fabric, or both, no matter the type. 

Length to Length Stretch - Vertical Stretch (V) 

Selvage to Selvage Stretch - Horizontal Stretch (H) 

These will be classified as a percetage out of 100%. 

1 WAY

This will have stretch along either the vertical or horizontal part of the fabric.  

2 WAY

This will have stretch along both the vertical and horizontal part of the fabric. 

4 WAY 

This is the same as a 2 Way, but it just makes reference to the inherit stretch along the bias/diagonal part of the fabric which is part of all fabrics! 

So, in conclusion - we refer to fabrics as having a horizontal or vertical (or both) stretch percentage and the recovery of the fabric once stretched to the max. If your pattern says 4 way stretch, you need to look for a 2 way fabric. 

Here's a little video by Zerrin further explaining this and showing some examples: https://www.youtube.com/watch?v=L4h49RC9oEU&t=36s