Here are a few definitions for sewing words and expressions used in the Camimade pattern instructions.
Baste / baste stitch: temporary stitching with a long stitch (4mm and more). Basting is used to maintain pleats in place before the final seam for instance or test the fit of a garment. This can be done by hand or with the sewing machine.
Clip: cutting snips in the seam allowances in order to have a clean result once you turn the fabric right side out. Clipping is important for curves, for necklines for instance. If the curve is concave, cutting simple snips is fine, and if the curve is convex, cutting triangle-shaped notches is more convenient to suppress fabric excess.
Facing: a piece of a garment that finishes an edge and stays inside the garment. Facings can be used to finish collars and armholes.
Finish seam allowances: in order to have a beautiful and long lasting finish inside your garments, it is nice to finish the seam allowances with a zig zag stitch or using an overlocker. This will ensure the fabric won’t fray and your garment will last after many washing.
Gathers: fine folds created using one or several rows of long stitches, allowing to get more volume in a part of a garment and to attach it to a smaller piece of garment. Gathering is often used to get some fullness on sleeves and attach them to armholes. It is often used for skirts too.
Grainline: the grainline is the direction in which the yarns are woven, parallel to the selvedges of the fabric. The pattern pieces include a straight line indicating the grainline and allowing you to position the pieces correctly on the fabric parallel to the selvedges. A good positioning of the grainline on the pattern pieces and fabric enable a garment to hang properly. On the contrary if the garment is cut off grain, it can result in twisting seams (you may have had a t-shirt that behaved like that!).
Interfacing: a layer of woven or non-woven material, often fusible (for home sewing at least). It is applied on the wrong side of the main fabric using the heat of the iron in order to give it body and stability, and prevent it from stretching. Collars, facings, button plackets, sleeves cuffs, etc, are often interfaced. Non-fusible interfacing is used in tailoring and has to be sewn in.
Right side / wrong side of the fabric: you will often see “right sides together” or “wrong sides together” in the pattern instructions. Your fabric has a right side, the side that will be visible from the outside of the garment, and a wrong side, the side which will stay inside the garment (unless a styling choice decides otherwise). When sewing, the most often situation is to put the fabric with right sides facing each other so that the seam allowances stay inside the garment. However there are cases when you have to put the fabric pieces wrong sides together, for French seams for instance. Following the instructions is key !
Seam allowances: distance from which one has to stitch the pieces of a garment together. They are included in Camimade patterns and are generally 1cm / 3/8” or 1.5cm / 5/8” depending on the pattern.
Selvedges (of the fabric): edges of the fabric that don’t fray. When you buy fabric, you get 2 edges that have been cut to give you the length you asked, and 2 “original” edges that correspond to the roll width of the fabric. Sometimes, selvedges show the designer name, the colour used for the print, and other details. When you cut a pattern, you generally have to lay the fabric selvedges against selvedges. The selvedges also help to find the grainline of the fabric.
Stay stitch: single line of stitching sewn on a curve to stabilise the fabric at the beginning of a project. It is generally used for necklines to prevent them from stretching.
Stitch in the ditch / sink stitch: attaching a garment piece inside the garment, stitching from the outside in an existing seam, so that the line of stitching stays invisible. It is one of my favourite techniques to sew the inside of a waistband or an inner back yoke.
Top stitch: top stitching are invisible lines of stitching used to reinforce a seam or decorate a garment, or both. Pockets can be top stitched to get both results.
Trim corners: cutting the seam allowances at 45 degrees near a corner in order to suppress fabric excess which would create bulkiness when turning the corner right side out.
Understitch: stitching a facing or a lining very close to an existing seam, making sure the seam allowances located on the other side are caught in the seam. This enables to fold and press the edges of a garment cleanly.