Weft

From Old English wefan ("to weave").

Full definition of weft

(plural wefts)

(weaving) The horizontal threads that are interlaced through the warp in a woven fabric.

1964 February 6, Kurt Greenwood, New looms that streamline weaving, New Scientist, page 356,It is all the more remarkable therefore that in one respect â€” weft colours â€” some of the pirnless looms are more versatile than conventional machines. Figure 6 shows the colour mechanism of a conventional loom designed to weave six colours of weft (there is never any problem about colour patterning in the warp).
1979, Eric Broudy, The Book of Looms: A History of the Handloom from Ancient Times to the Present, page 81,Other techniques for shaping included angling one or both loom bars, adding extra wefts, or adjusting warp tension.
1993, Anni Albers, On Weaving, note on Plate 17, page 48,To give greater firmness to the basket-weave plain weave, thin weft threads can be introduced that will be covered by the heavier pattern wefts of the basket weave.

(weaving) The yarn used for the weft; the fill.
(hairdressing) A hair extension that is glued directly to a personâ€²s natural hair.

2009, Cosmetologists, 150 Great Tech Prep Careers, 2nd Edition, page 135,Teaching tools include mannequins, slip-ons, hair wefts, rectangles, and profiles.
2011, Ryan Rayston, The Quiet Sound of Disappearing, AuthorHouse, page 289,Then, she held up the hair as it would look on my head. She positioned it like a pro, holding wefts of human hair so that it looked like it grew from my scalp.
2012, Cengage Learning, Milady Standard Cosmetology, page 556,In the bonding method of attaching hair extensions, hair wefts or single strands are attached with an adhesive or bonding agent. The adhesive is applied to the weft with an applicator gun.

Compare waif.

(plural wefts)