Cis-natural antisense transcript refers to a type of RNA molecule that is transcribed from the same DNA locus as its "sense" counterpart, but in the opposite direction. This type of transcript has been implicated in a variety of biological processes, such as alternative splicing, RNA interference, and gene regulation. Some possible synonyms for this term include cis-antisense transcript, NAT, and endogenous antisense RNA. Researchers studying these transcripts may also use related terms, such as sense-antisense pairs or convergent transcription. Understanding the functions and mechanisms of cis-natural antisense transcripts could have important implications for our understanding of gene expression and disease pathology.