Definition of bacterium in English:

bacterium

Line breaks: bac|ter¦ium
Pronunciation: /bakˈtɪərɪəm
 
/

noun (plural bacteria /-rɪə/)

  • A member of a large group of unicellular microorganisms which have cell walls but lack organelles and an organized nucleus, including some which can cause disease.
    More example sentences
    • A urine test can also be used to confirm that the bacteria are the Legionella bacteria.
    • The pneumococcal bacterium is the second most common cause of bacterial meningitis.
    • Typhoid fever is a serious infection caused by the bacterium Salmonella typhi.

Bacteria are widely distributed in soil, water, and air, and on or in the tissues of plants and animals. Formerly included in the plant kingdom, they are now classified separately (as prokaryotes). They play a vital role in global ecology, as the chemical changes they bring about include those of organic decay and nitrogen fixation. Much modern biochemical knowledge has been gained from the study of bacteria, as they grow easily and reproduce rapidly in laboratory cultures

Derivatives

bacterial

adjective
More example sentences
  • Nevertheless, some viable bacterial cells and bacterial and fungal spores are present.
  • Vaccines are made from killed bacteria, detoxified bacterial toxins, or modified viruses.
  • Some illnesses, such as ear infections and diarrhoea, may be either bacterial or viral.

bacterially

adverb
More example sentences
  • A particularly impressive bacterially controlled mineral is produced by magnetotactic bacteria, which can detect magnetic fields.
  • During burial much of the organic carbon is further degraded bacterially, leaving the burial flux.
  • In clean procedures, no bacterially colonized area of the body is opened, so it generally is believed that postoperative wound infection occurs because of problems in the surgical environmental or the surgeon's inexperience.

Origin

mid 19th century: modern Latin, from Greek baktērion, diminutive of baktēria 'staff, cane' (because the first ones to be discovered were rod-shaped). Compare with bacillus.

Usage

Bacteria is the plural form (derived from Latin) of bacterium. Like any other plural it should be used with the plural form of the verb: the bacteria causing salmonella are killed by thorough cooking , not the bacteria causing salmonella is killed by thorough cooking . However, the unfamiliarity of the form means that bacteria is sometimes mistakenly treated as a singular form, as in the example above.

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