Quilt block glossary
Finished size, sewn unfinished trim size and starting cut size name three different states. This glossary anchors those terms and every unit name used by the current block geometry, so a chart can link to one definition instead of guessing.
Scroll sideways to inspect every label.
- Finished size: after surrounding seams.
- Sewn unfinished / trim size: assembled before those seams.
- Starting cut size: method-specific fabric input.
The units
- flying-geese unit
- A rectangle holding one large triangle pointing along its length, with a smaller triangle in each corner. It finishes exactly twice as wide as it is tall. Used by 2 of the 18 blocks in this library.
- half-square-triangle unit
- A square made of two right triangles joined on the diagonal. You cut squares, sew, and subcut — never cut loose triangles. Used by 11 of the 18 blocks in this library.
- quarter-square-triangle unit
- A square made of four right triangles meeting in the centre, like an hourglass crossed with its mirror. Cut from squares subcut on both diagonals. Used by 2 of the 18 blocks in this library.
- rectangle
- A plain rectangle of one fabric, used whole. Used by 3 of the 18 blocks in this library.
- square-in-a-square unit
- A centre square set on point inside four corner triangles, so the finished unit frames the square. Cut from a centre square plus corner squares subcut on the diagonal. Used by 1 of the 18 blocks in this library.
- square
- A plain square of one fabric, used whole — the unit every other one builds on. Used by 11 of the 18 blocks in this library.
- strip
- A long, narrow rectangle, used whole. Log Cabin and Rail Fence are built entirely from strips. Used by 2 of the 18 blocks in this library.
The words the site uses
- finished size
- The size of a block or unit after every seam around it is sewn. It is always smaller than the piece you cut, and it is the size patterns usually name. Used by every chart heading and size input.
- unfinished size
- The assembled block or unit before the surrounding seams are sewn — the finished size plus ½″. It is the sewn-unfinished trim target, not a universal starting cut. Used by assembled-unit trim targets, square-up checks and pre-outer-seam measurements.
- starting cut size
- The fabric piece a method begins with. It equals the sewn-unfinished size for a plain square or rectangle, but triangle and pieced-unit methods often start from larger squares. Used by cutting-chart inputs before assembly.
- seam allowance
- The fabric between the stitching line and the cut edge — a quarter inch in quilt piecing. Every cut size on this site already includes it on each edge. Used by every cutting formula on the site.
- grid
- The count of equal divisions a block is drawn on — a 3×3 block is three units across and three down. The grid decides which finished sizes divide cleanly. Used by every block page’s facts list and the size calculator.
- unit
- One cell of the grid: a square, a rectangle, a strip, or a pieced patch such as a half-square-triangle unit. Charts give cut sizes per unit; the block is sewn from units. Used by every chart row and piecing step.
- subcut
- A second cut made across a piece you have already cut — usually cutting a square on one or both diagonals to make triangles. Used by the triangle rows of every cutting chart.
- width of fabric
- The width of quilting cotton as it comes off the bolt. Yardage on this site assumes 40″ of that width is usable once the selvedges are gone. Used by every yardage figure.
- sashing
- The strips of fabric between the blocks in a quilt top. The quilt size calculator adds them between every row and column. Used by the quilt size calculator.
- cornerstone
- The small square where two sashing strips cross. One sits at every intersection when sashing is used. Used by the quilt size calculator.
- border
- The frame of fabric around the outside of the quilt top, added after the blocks and sashing are joined. Used by the quilt size calculator.
- calibration square
- The 1-inch test square printed on every printable page. Measure it with a ruler before you cut — if it is not exactly 1 inch, the printer scaled the page. Used by every printable page.
The blocks these terms describe
Every block page uses this vocabulary in its chart, its facts list and its piecing steps.
- Bear's Paw
- Broken Dishes
- Card Trick
- Churn Dash
- Flying Geese
- Friendship Star
- Heart
- Jacob's Ladder
- Log Cabin
- Maple Leaf
- Nine Patch
- Ohio Star
- Pinwheel
- Rail Fence
- Sawtooth Star
- Shoofly
- Sister's Choice
- Square in a Square
Related pages
- Finished vs unfinished block size Keep finished, sewn unfinished, and starting cuts distinct.
- The quarter inch seam allowance See what the seam removes and test it.
- How to square up a quilt block Check and trim a pieced block.
- Printing quilt patterns at 100% Calibrate the one-inch square before cutting.
- Half square triangle blocks Browse every HST-bearing block and its terminology.
- Quilt block sizes Compare clean steps, cuttable eighths, and refused sizes.
Common questions
What is a half square triangle?
A square made of two right triangles sewn together on the diagonal. You cut squares, sew, then subcut; you never cut the triangles loose. The half square triangle blocks page lists every block here that uses them.
What does finished size mean?
The size of a block or unit after every seam around it is sewn — always smaller than the piece you cut. The finished and unfinished size guide distinguishes it from the sewn trim target and from method-specific starting cuts.
What is width of fabric?
The width of quilting cotton as it comes off the bolt, selvedge to selvedge. Every yardage figure on this site assumes 40″ of usable width, and says so beside the answer.