The best magazine
: Working a purl 3 together (p3tog).){kind=link}
Like purl 2 together, purl 3 together is a decrease performed on the purl or (typically) wrong side of a knitting project that slants to the right. In this case you are decreasing two stitches at once instead of just one.
To make this decrease, start by going into the third stitch as they sit on the left-hand needle, followed by the second and the first, as if to purl.
Complete the purl stitch as if they were all one stitch.
Two stitches have been decreased.
Source: ...