The speed of an object is the magnitude of the change of its position.

Spent fuel pools are storage pools for spent fuel from nuclear reactors.

The specific weight, also known as the unit weight, is the weight per unit volume of a material.

Specific kinetic energy is kinetic energy of an object per unit of mass.

In thermodynamics, the specific volume of a substance is an intrinsic property of a substance, defined as the ratio of the substance's volume (V) to its mass (m).

Heat capacity or thermal capacity is a physical property of matter, defined as the amount of heat to be supplied to a given mass of a material to produce a unit change in its temperature.

Specific energy or massic energy is energy per unit mass.

An internal combustion engine where a fuel/air mixture is drawn into a cylinder and ignited by a spark during compression.

A spark plug is a device for delivering electric current from an ignition system to the combustion chamber of a spark-ignition engine to ignite the compressed fuel/air mixture by an electric spark, while containing combustion pressure within the engine.

A spar is a marine structure, used for floating oil/gas platforms.

Spallation is the process in which a heavy nucleus emits numerous nucleons as a result of being hit by a high-energy particle, thus greatly reducing its atomic weight.

Space-based solar power (SBSP) is the concept of collecting solar power in outer space and distributing it to Earth.

A space heater is a device used to heat a single, small area. Space heaters are powered by electricity or a burnable fuel, such as natural gas, propane, fuel oil, or wood pellets.

In petroleum geology, source rock is rock which has generated hydrocarbons or which could generate hydrocarbons.

Sour gas is natural gas or any other gas containing significant amounts of hydrogen sulfide (H2S).

Measured in decibels it is used to establish the noise level in an area or in the disgn of an area that will contain high noise. The measured results are primarily used to ensure that working areas comply with legislation on noise levels and to advise workers on the type of noise suppression protective equipment is required.

The acoustic energy emitted by a source as a pressure wave

A solvent (from the Latin solvō, "loosen, untie, solve") is a substance that dissolves a solute, resulting in a solution.

Solvation (or dissolution) describes the interaction of solvent with dissolved molecules.

Suggestions to achieve an end goal or alternatives to existing processes.