Definition of "HST"

(UK, rail transport) Initialism of High Speed Train, a common name for the InterCity 125.  examples

(Canada) Initialism of harmonized sales tax, a combined federal and provincial sales tax collected in some provinces.  examples

(quilting) Abbreviation of half-square triangle.  examples

(nautical) Initialism of high speed transport.  examples

Initialism of Hawaiian Standard Time.  examples

(space science, US, NASA) Initialism of Hubble Space Telescope.  examples