The phrase "tight weave" refers to a fabric or material that has been woven tightly, with very little space between the threads. This creates a sturdy and strong texture, making it harder for things to pass through or for the material to tear.
The European loop (see photo), works best with long small to medium wide knit scarves or oblong wool or polyester scarves with tight weave. (highlatitudestyle.com)
Tighter woven fabrics, like hemp, will not work with the snappi fastener - it can not get a grip of the cloth diaper to secure it around baby. (diaperjunction.com)