This is typically something you can fold over or tuck in.

Thisis what Vinterberg & Bodelsen suggest:

snip en -per
corner (fx a corner of her handkerchief);
end (fx of a scarf);
point (fx he pulled down the points of his waistcoat);
(fx på konvolut) flap;
(lap på skosål) patch;
...

There are lots of examples in paper-folding exercises for making Christmas decorations where you tuck in in a corner or glue down a flap, which is a 'snip' in this sense.

I don't know if there is some layer that has to be folded or tucked in on a wind turbine blade, but it would not surprise me.
Everything does have to be neatened and smoothed off to reduce air resistance.