Trimethylamine is an organic compound
Organic compound
An organic compound is any member of a large class of gaseous, liquid, or solid chemical compounds whose molecules contain carbon. For historical reasons discussed below, a few types of carbon-containing compounds such as carbides, carbonates, simple oxides of carbon, and cyanides, as well as the...

 with the formula N(CH3)3. This colorless, hygroscopic, and flammable tertiary amine has a strong "fishy" odor
An odor or odour is caused by one or more volatilized chemical compounds, generally at a very low concentration, that humans or other animals perceive by the sense of olfaction. Odors are also commonly called scents, which can refer to both pleasant and unpleasant odors...

 in low concentration
In chemistry, concentration is defined as the abundance of a constituent divided by the total volume of a mixture. Four types can be distinguished: mass concentration, molar concentration, number concentration, and volume concentration...

s and an ammonia
Ammonia is a compound of nitrogen and hydrogen with the formula . It is a colourless gas with a characteristic pungent odour. Ammonia contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to food and fertilizers. Ammonia, either directly or...

-like odor at higher concentrations. It is a gas at room temperature but is usually sold in pressurized gas cylinder
Gas cylinder
A gas cylinder is a pressure vessel used to store gases at above atmospheric pressure. High pressure gas cylinders are also called bottles. Although they are sometimes colloquially called "tanks", this is technically incorrect, as a tank is a vessel used to store liquids at ambient pressure and...

s or as a 40% solution
In chemistry, a solution is a homogeneous mixture composed of only one phase. In such a mixture, a solute is dissolved in another substance, known as a solvent. The solvent does the dissolving.- Types of solutions :...

 in water.

Trimethylamine is a product of decomposition of plants and animals.