Wiktionary(0.00 / 0 votes)Rate this definition: 1  sergeant(Noun) UK army rank with NATO code OR-6, senior to corporal and junior to warrant officer ranks. 2  sergeant(Noun) The highest rank of noncommissioned officer in some non-naval military forces and police.
Organism: is an individual living thing, such as a plant, animal, bacterium, protest, or fungus. An organism has a body made up of smaller parts that work together. There are many different organisms. Some scientist estimate there to be as many as 100,000 different organisms on Earth. Sometimes organisms are grouped by the environment they live in. For example, marine organisms live in the ocean.
An ericoid mycorrhizal fungus. In biology, an organism is any contiguous living system, such as an animal, plant, fungus, archaeon, or bacterium. All known types of organisms are capable of some degree of response to stimuli, reproduction, growth and development and homeostasis. An organism consists of one or more cells; when it has one cell it is known as a unicellular organism; and when it has more than one it is known as a multicellular organism. Most unicellular organisms are of microscopic size and are thus classified as microorganisms.