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.
How Spliceosomes Process RNA. What is the purpose of introns? DNA is composed of sections known as exons and introns. The exons are the portions that eventually exit the nucleus in the form of mRNA and are used in translation. The introns are removed from the mRNA shortly after transcription. There are a number of hypotheses about the function of introns.