Webster's Revised Unabridged Dictionary · 1913

octamer

octamer (ok"tu*mẽr) , noun

[Octa- + Greek me`ros part.]

(Chemistry) A molecule composed of eight monomer units bound to each other, usually in a linear array; as, an octamer formed from eight nucleotides is called an octanucleotide.

An example of an octapeptide might be represented using the standard abbreviations for the component amino acids, for example: met-ala-ser-glu-lys-ala-val-gly

An octanucleotide might be represented using the standard single-letter abbreviations for the component mononucleotides, for example: ATGCATGC.