YAC  ( Yeast artificial chromosome )
 

- Constructed from yeast DNA, it is a vector used to clone large DNA fragments.
Definition from:
Genome Glossary

- Originating from a bacterial plasmid; a YAC contains additionally a yeast centromeric region (CEN); a yeast origin of DNA replication (ARS); and two telomere regions (TEL). YACs are capable of cloning very large pieces of DNA.
Definition from:
http://www.biochem.northwestern.edu/holmgren/Glossary/Definitions/Def-Y/YAC.html