HST
HST turns up in 2 fields: railroad, textiles. Here is what it means to the people in each one.
HST in railroad
High-speed train, referring to passenger services operating significantly faster than conventional rail.
High-speed train. A passenger service designed for sustained velocities well above standard freight and commuter traffic, requiring specialized rolling stock, dedicated track alignments, and advanced signaling. While North American rails primarily host mixed traffic, these dedicated fast corridors use tilt technology and overhead catenary to achieve rapid transit between major urban centers.
"The dispatcher is holding us in the siding so the HST can blow past."
HST in textiles
Half-square triangle, a common geometric unit in patchwork quilting.
A half-square triangle is a quilt block made of two right-angled triangles joined along their long diagonal edges to form a two-color square. Quilters usually mass-produce them by placing two fabric squares right sides together, sewing two parallel lines down the center diagonal, and cutting between the stitches. They form the basis of thousands of traditional quilt patterns.
"We're making sixty HST units for the border of the star quilt."