1) A group of overlapping clones representing regions of the genome; the contiguous sequence of DNA created by assembling these overlapping chromosome fragments.

2) Group of cloned (copied) pieces of DNA representing overlapping regions of a particular chromosome.

3) A contig--from the word "contiguous"--is a series of overlapping DNA sequences used to make a physical map that reconstructs the original DNA sequence of a chromosome or a region of a chromosome. A contig can also refer to one of the DNA sequences used in making such a map.