What does it mean to 'tack' during piece assembly

I crocheted a bookmark that is done in one long piece. In order to make the final cross shape, the pattern says to glue the parts that overlap. The problem is that there is a section where 4 corners meet and its says to 'tack' them together. Am i supposed to glue them or does it mean sew the corners together?


It would be helpful if you have a link to a pattern if it is something you got from the Internet.

Did you complete 2 rectangles that you will be overlapping to form a cross? I cannot visualize how you would have four corners meeting unless you are doing some kind of shaping by folding a square or shape other than a rectangle. References to tack in needle work usually means to connect pieces together at a specific point -- whether by sewing a stitch or gluing a small spot.