What is "thermal cycler"

n. (context genetics English) A laboratory device in which a polymerase chain reaction is carried out repeatedly in cycles which in turn amplifies the sample DNA segments. The instrument contains a thermal block which contains the DNA samples and can precisely control the internal temperature.

The thermal cycler (also known as a thermocycler, PCR machine or DNA amplifier) is a laboratory apparatus most commonly used to amplify segments of DNA via the polymerase chain reaction (PCR). Thermal cyclers may also be used in laboratories to facilitate other temperature-sensitive reactions, including restriction enzyme digestion or rapid diagnostics. The device has a thermal block with holes where tubes holding the reaction mixtures can be inserted. The cycler then raises and lowers the temperature of the block in discrete, pre-programmed steps.