Dna (noun)

1. A nucleic acid that is the main component of chromosomes and is the material that transfers genetic characteristics in all life forms; it consists of two long chains of nucleotides twisted together into a double helix and joined by hydrogen bonds between the complementary bases adenine and thymine or cytosine and guanine.
2. A similar substance or a piece of genetic material in some viruses.

Origin:

From the initial letters of the terms deoxyribonucleic acid.

Examples:

1. Scientists have been able to map the entire human DNA.
2. The DNA of the virus was analyzed to determine its origin.
3. The DNA of the sample matched the DNA of the suspect.
4. The DNA in the cells of our body determines our physical characteristics.
5. DNA is the blueprint for all living organisms.