Glossary

armscye	the part of the garment that the sleeve will be sewn into
bias	also called cross-grain. Instead of the normal orientation of the fabric, this is at 45 degrees to the grain
dart	a dart shapes a garment. A dart is formed by pinching off excess fabric and sewing along to keep the sections together. Darts can be tapered to one or both ends. A pleat sometimes acts as an open dart that hasn't been sewn shut
fold	Usually referred to as 'on the fold': you fold the fabric lengthwise and cut the left and the right half of a pattern piece in one, on the fold, without cutting a centre seam
grain	the direction of the fabric: either in the direction of the warp (lengthwise grain) or the weft (crosswise grain)
muslin	a) or toile: a first draft or trial version of a garment in an inexpensive fabric to check for fit. Alterations can be drawn on and then transferred to the pattern to be used with the final fabric - b) a type of fabric (the calico type can be used to make a muslin as in a) )
nap	the pile of a fabric that can be brushed in one direction, e.g. on corderoy or fur. Take care to cut all pattern pieces with the nap or pile oriented in the same direction
notch	a marking on your dressmakig pattern often in a diamond shape. Notches are used to match seams of adjacent pattern pieces in the right places. They can be cut outward or marked with chalk, tailor tacks, a frixion pen etc
pleat	a fold in the fabric sewn into place at the top, or partially sewn down and then allowed to spring open. A dart is a pleat that was sewn shut along its full length
wearable muslin	see: muslin (a). A muslin made with the aim of being able to wear this draft version although it will be made a second time in the intended fabric
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To be continued. Feel free to add terms. Use the 'HTML' tab to use the table formatting, just copy from another row.