overlock threads – threads typically provided on large and economical cones meant for overlock/serger and coverstitch machines. They are usually more rough in structure. In general, they should not be used in regular sewing machines, especially the more advanced models which require quality thrads to run smoothly on a long run.
knit (fabric) – fabric created by pulling one yarn loop through another loop. Most knits stretch thanks to that structure. Read more Dealing with fabrics
ironing – using an iron to remove wrinkles from fabric or garment, in a sliding motion. Read about differences between ironing and pressing in Pressing.
interfacing – additional layer added to the wrong side of a fashion fabric to support the shape of a garment piece and add body. Traditional interfacings are sewn-in, the modern ones are usually fusible. Read more Interfacing
hem – the common way of finishing the bottom and sleeve edges of garments by folding some extra fabric to the wrong side. Hem can be a single fold or a double fold. It is usually top-stitched or blind-stitched.
fold (of fabric) – the edge created by bending one layer of a fabric over itself so that one layer covers another. Symmetrical parts of garments are cut on fold of a fabric to make sure that both sides are symmetrical. Find more Fabric cutting
feed dogs – teeth-like elements located in a machine throat plate, which transport the fabric under the machine foot while sewing by moving back and forth.
edgestitching – (top)stitching very close to the folded or sewn edge. Edge-stitching is done usually to stabilize the edge or for decorative purposes.
dart – one of the most important garment construction concepts. Darts add the third dimension to otherwise flat fabrics. They are triangular or diamond-shaped folds of fabrics, tapering to nothing at the end(s). They take care of the depth/fullness of the garment.
bobbin – a small spool onto which you need to wind a thread, usually referring to a spool on which the lower thread of the sewing machine is wound. The machine makes a stitch by catching the bottom/lower thread (from the bobbin) with the top thread (from the needle).