contig

A contig (short for "contiguous sequence") is a technical term used primarily in genomics and bioinformatics. While you might use the adjective contiguous to describe things that touch or run together—like "houses built contiguously along a street"—a contig is the noun for the single, continuous block formed when overlapping pieces are combined.

In genetics, a contig is a DNA sequence where overlapping fragments have been assembled to create a longer, uninterrupted stretch of genetic code. Think of it like piecing together a jigsaw puzzle: each fragment is a small piece of the genome, and when the pieces overlap and connect, they form a larger, more complete picture—that's your contig. Scientists use contigs as essential building blocks for assembling entire genomes. The longer and more reliable a contig is, the more confident scientists can be in the accuracy of their genetic map.

Outside DNA work, you may also see contig used more loosely for a single continuous span created from smaller pieces (for example, in some computing contexts). However, it is important to remember the distinction: if you are describing the state of being adjacent or unbroken, use contiguous. If you are referring to the resulting unified sequence or segment itself, you are talking about a contig—a seamless joining of parts into one continuous whole.