meso-, mes-, mesi-

(Greek: middle, intermediate; close to a center line; between)

mesopic, mesopic vision
A reference to the combination of photopic vision and scotopic vision in which there are low but not quite dark lighting situations.
mesoplankton (s) (noun), meroplankton (pl)
A plant or animal organism of intermediate body size, between macroplanktons, which are large, and microplanktons, that are very small: The mesoplankton thrive between about a hundred fathoms from the bottom of the sea and a hundred from the surface, or between the epiplanktonic and bathyplanktonic levels.
Referring to the nucleus of a cell.
Any large plant floating freely between the surface and the floor of a lake.
1. An ancient region of southwest Asia between the Tigris and Euphrates rivers in modern-day Iraq.

Probably settled before 5000 B.C., the area was the home of numerous early civilizations, including Sumer, Akkad, Babylonia, and Assyria.

It diminished in importance after the Mongol invaders destroyed its extensive irrigation system in A.D. 1258.

2. Etymology: from Ancient Greek ??????????? (Mesopotamía); from ????? (mésos, "between, middle") + ??????? (potamós, "river"), because Mesopotamia is located between the Euphrates and Tigris rivers.

The geography of the area allowed for the development of husbandry, agriculture, and permanent settlements.

Trade with other regions also flourished irrigation techniques were created as well as pottery and other crafts building methods based on clay bricks were developed and elaborate religious cults evolved.

It was the two rivers that became the basis upon which the wealth of the region was based and through relatively easy irrigation, agriculture could yield heavy crops.

1. A reference to the area of Mesopotamia.
2. A native or inhabitant of Mesopotamia (the larger part of which is now Iraq).
A district between two rivers.
1. Those organisms living in, or moving between, sand.
2. Those organisms living in the interstitial (small openings, gaps, or cracks) spaces of a sandy sediment.
Prepenna following protoptile and succeeded by metaptile or by teleoptile.
mesorchium, mesorchial
1. Peritoneal fold supporting the testis in the fetus.
2. In the fetus, a fold of tunica vaginalis testis (the serous membrane surrounding the front and sides of the testicle) supporting the mesonephros and the developing testis.
3. In the adult, a fold of tunica vaginalis testis between the testis and epididymis.
Situated between the nostrils having a nasal index between 48 and 53 or the ratio of the width to the height of the nose, multiplied by 100, used in anthropological measurements.
mesorrhine, mesorhine
1. A person or skull having a nasal index intermediate between leptorrhine and platyrrhine.
2. Having a nose of moderate width.
A biological classification of water quality according to the following categories:
  • Oligosaprobic, clear, with no or only slight pollution and high dissolved oxygen.
  • Mesosaprobic, moderately polluted; polysaprobic, strongly polluted.
  • Antisaprobic, so polluted that no living organism is capable of living in the water.
1. Referring to a polluted aquatic habitat having reduced oxygen concentration and a moderately high level of organic decomposition.
2. Designating, relating to, or characteristic of running water which is partially polluted.
1. An order of extinct aquatic reptiles which is known from a single genus, Mesosaurus, characterized by a long snout, numerous slender teeth, small forelimbs, and webbed hind feet.
2. An order of small marine reptiles that lived during the early Permian period, roughly 299 to 280 million years ago.