a link or loop or knot made by an implement in knitting, crocheting, embroidery, or sewing
"She carefully counted each stitch to ensure the sweater would fit perfectly."
a sharp spasm of pain in the side resulting from running
"He had to slow down after feeling a stitch in his side while sprinting up the hill."
A single pass of a needle in sewing; the loop or turn of the thread thus made.
"She carefully counted each stitch to ensure the seam was even and strong."
In plain English: A stitch is a single loop of thread used to sew fabric together by hand or with a machine.
"She had to get stitches after falling and cutting her leg on broken glass."
Usage: Use "stitch" to refer to an individual unit of sewing work rather than the entire seam, which is called a stitchline. Distinguish it from related terms like "seam," which describes the joined edges themselves, and avoid using it as a verb when you simply mean to sew without specifying the method.
fasten by sewing; do needlework
"She sat quietly to stitch a button onto her shirt while waiting for the bus."
To form stitches in; especially, to sew in such a manner as to show on the surface a continuous line of stitches.
"The tailor carefully stitched the seam so that the thread formed a neat, continuous line across the fabric's surface."
In plain English: To stitch is to join two pieces of fabric together by pushing a needle and thread through them repeatedly.
"She decided to stitch her torn jeans back together before going out tonight."
The word "stitch" comes from the Proto-Indo-European root (s)teyg-, meaning "to stab or pierce," which entered Middle English as stiche* to describe a sharp pain in the side caused by such an action. Over time, this original sense of a piercing sensation evolved into its modern definition referring specifically to a looped thread used for sewing fabric together.