EOR stands for every other row, or every other round. It directs the crafter to apply a specific shaping technique, such as an increase or decrease, on one row and then work the next row plain without shaping. This creates a gradual slope in the fabric, commonly used for shaping sleeves and necklines.
Heard on the job
Decrease one stitch at each edge EOR until you have forty stitches left on the needles.