Share this entry
plasmid Line breaks: plas|mid
Pronunciation: /ˈplazmɪd/

Definition of plasmid in English:


A genetic structure in a cell that can replicate independently of the chromosomes, typically a small circular DNA strand in the cytoplasm of a bacterium or protozoan. Plasmids are much used in the laboratory manipulation of genes. Compare with episome.
Example sentences
  • The bacterium contains a plasmid, a circular piece of DNA that holds the gene and promoter sequence.
  • The replication control genes of bacterial plasmids face selection at two conflicting levels.
  • We note, however, that few if any of the genes borne by bacterial plasmids are under strong positive selection at all times.


1950s: from plasma + -id2.

Definition of plasmid in:
Share this entry

What do you find interesting about this word or phrase?

Comments that don't adhere to our Community Guidelines may be moderated or removed.

Subscribe to remove ads and access premium resources