"yo through the back loop"

I know how to do a yarn over, but what does “yo through the back loop” mean? Does it mean to pull the yarn forward as if to do a normal yo, then insert the needle through the back of the stitch instead of the front, and knit as usual? - like pull the yarn forward, then do a “knit in the back loop”?

Hi! Without reading the pattern it’s kind of hard to say. Could you link to the pattern?

This would be my guess, but having a link to the pattern would help.

It is downloaded in pdf, but here is the exerpt - it is in the paragraph “hat body” round 3:

Hat Band:
Round 1: *k1, p1, repeat all around.
Round 2: *p1, k1, repeat all around.
Repeat rounds 1-2 for a total of 5 rounds.
Switch to the main color (grey pictured).

Hat body:
Round 1: k2tog, knit all stitches to end. (32, 36, 40 sts)
Round 2. *k4, yo, repeat from * all around.
Round 3. *k4, knit yo through the back loop, repeat from * all around.
(40, 45, 50 sts)

Thanks!

You’ve made the yarn over on the previous round, round 2. On round 3, when you come to the yarn over, knit it through the back loop. You’ll work it like knitting any stitch through the back loop which will close up the yarn over hole.
Thanks for the quote. The context really helps.