Reuptake is defined as the process by which neurotransmitters are reabsorbed by the presynaptic nerve endings after being released into the synaptic cleft. Some synonyms for reuptake include uptake, reabsorption, and recycling. Uptake refers to the process by which molecules are moved from the extracellular fluid into the cell. Reabsorption describes the recovery of substances that have already been filtered in the kidneys or intestines. Recycling refers to the reuse of certain materials after they have been processed and broken down. All of these terms describe different aspects of the reuptake process, and can be used interchangeably, depending on the context.