hauberk (plural hauberks) A coat of mail; especially, the long coat of mail of the European Middle Ages, as contrasted with the habergeon, which is shorter and sometimes sleeveless. 1786, Francis Grose, A Treatise on Ancient Armour and Weapons, page 14: The hauberk was a complete covering of mail from head to foot. It consisted of a hood, joined to a jacket with sleeves, breeches, stockings and shoes of double chain mail, to which were added gauntlets of the same construction.
1 Exons are expressing sequences within a pre-mRNA molecule that are spliced together once introns are removed to form mature mRNA molecules that are translated into proteins.  Alternative splicing allows for the production of various protein isoforms from one single gene coding.
Simple illustration of exons and introns in pre-mRNA and the formation of mature mRNA by splicing. In molecular biology and genetics, splicing is a modification of the nascent pre-messenger RNA (pre-mRNA) transcript in which introns are removed and exons are joined. For nuclear-encoded genes, splicing takes place within the nucleus after or concurrently with transcription.