what doe4s this stitch pattern mean?

[uniquo]

when it says "Mulitple of 6 + 3"

does it mean 6 stitches + 3 for ease?

[mwhite]

It means that you must cast on a total of 9 sts. to do the pattern once. If, for example you want to make 10 repeats of the pattern, you would cast on a total of 63(6 x 10 + 3). The + number actually balances the pattern.

[Spokaloo]

The "+3" is usually for a border or to enable you to begin or finish a repeat without just leaving something hanging. For example, if your pattern is simply k2tog, yo, k2tog, yo, repeat to end. How would you end it? You can't just have a yo at the end of the row! It would just fall off your needle! So the pattern tells you to cast on a multiple of 2 + 1 which gives you a stitch at the end of the row to hold that yo on.