Bartending terminology
Various unique terminology is used in bartending.
Drink preparation
In bartending, the term "straight up" (or "up") refers to an alcoholic drink that is shaken or stirred with ice and then strained and served without ice in a stemmed glass.
This is contrasted with a drink served "neat" – a single, unmixed liquor served without being chilled and without any water, ice, or other mixer. Neat drinks are typically served in a rocks glass, shot glass, snifter, Glencairn glass or copita.
"On the rocks" refers to liquor poured over ice cubes, and a "rocks drink" is a drink served on the rocks. Rocks drinks are typically served in a rocks glass, highball glass, or Collins glass, all of which refer to a relatively straight-walled, flat-bottomed glass; the rocks glass is typically the shortest and widest, followed by the highball which is taller and often narrower, then the Collins which is taller and narrower still.
The terms "straight" and "straight up" can be ambiguous, as they are sometimes used to mean "neat"; "up" is less ambiguous.