Also found in: Medical.
n. Abbr. poly(A)
A polymer of adenosine nucleotides that is often attached to eukaryotic messenger RNA and stabilizes the molecule before transport from the nucleus into the cytoplasm.
pol′y•ad•e•nyl′ic ac′id(ˈpɒl iˌæd nˈɪl ɪk, ˌpɒl-)
a segment of nucleotides composed of adenylic acid residues, appearing at the tail end of messenger RNA after transcription and inducing stability: added to DNA fragments in certain genetic engineering procedures. Also called poly A.