Definition: A tablespoon per second (Tbs/s) is a unit of volumetric flow rate representing one tablespoon of substance passing a point in one second. It measures small volumes with slightly larger increments than teaspoon measurements.

History/origin: The tablespoon is a common household measure of volume, and combining it with 'per second' allows for quantifying the flow of small amounts of liquid or granular substances. The origins of the tablespoon as a unit of measure are informal, based on household usage.

Current use: Tbs/s can be used in pharmaceutical applications, small-scale chemical processes, and cooking/baking scenarios where precisely controlling the flow of small quantities is necessary, though in slightly larger increments than tsp/s. It's used for measuring the flow of viscous liquids.