grade

views updated Jun 08 2018

grade / grād/ • n. 1. a particular level of rank, quality, proficiency, intensity, or value: sea salt is usually available in coarse or fine grades. ∎  a level in a salary or employment structure. ∎  a mark indicating the quality of a student's work: I got good grades last semester. ∎  (with specifying ordinal number) those students in a school or school system who are grouped by age or ability for teaching at a particular level for a year: she teaches first grade. ∎  a level of quality or size for food or other products: grade AA butter. ∎  (in historical linguistics) one in a series of related root forms exhibiting ablaut. ∎  Zool. a group of animals at a similar evolutionary level.2. a gradient or slope: just over the crest of a long seven percent grade.3. [usu. as adj.] a variety of cattle produced by crossing with a superior breed: grade stock.• v. [tr.] (usu. be graded) 1. arrange in or allocate to grades; class or sort: they are graded according to thickness | [as adj.] (graded) carefully graded exercises. ∎  give a mark to (a student or a piece of work).2. [intr.] pass gradually from one level, esp. a shade of color, into another: the sky graded from blue to white on the horizon.3. reduce (a road) to an easy gradient.4. cross (livestock) with a superior breed.PHRASES: at grade on the same level: the crossing at grade of two streets.make the grade inf. succeed; reach the desired standard.

grade

views updated May 08 2018

grade
1. Group of things all of which have the same value.

2. A balanced condition, especially of a river (river or stream grade) when it has just sufficient energy to transport the load supplied from the drainage basin; a balance between erosion and deposition. The concept has also been applied to hillslopes (‘graded slopes’) that are stable dynamically and so maintain themselves in the most economical configuration. The term is no longer used widely as it oversimplifies the issues involved.

3. The fraction of a sediment falling within a particular size limit, e.g. sand grade, silt grade, and boulder grade. See PARTICLE SIZE.

4. The quality of a mineral ore.

5. Classification of an ore by the quantity or purity of the mineable metal in an orebody.

6. In civil engineering, the gradient of a road.

7. Distinctive functional or structural level of complexity in the organization of an organism. Thus fish, amphibians, reptiles, and mammals represent successive vertebrate grades. Grades may occur within a single lineage; or the same grade may be achieved independently in different ones (e.g. warm-bloodedness evolved independently in birds and mammals).

8. See METAMORPHIC GRADE.

grade

views updated Jun 27 2018

grade
1. A group of things all of which have the same value.

2. A distinctive functional or structural improvement in the organization of an organism. Thus fish, amphibians, reptiles, and mammals represent successive vertebrate grades. Grades may occur within a single lineage or the same grade may be achieved independently in different ones (e.g. warm-bloodedness evolved independently in birds and mammals).

3. The fraction of a sediment that falls within a particular size limit (e.g. sand grade, silt grade, and boulder grade).

4. The quality of a mineral ore (i.e. the classification of an ore by the quantity or purity of the mineable metal in an ore body.

5. In civil engineering, the gradient of a road.

6. A balanced condition, especially of a river (river or stream grade) that has just sufficient energy to transport the load supplied from the drainage basin; a balance between erosion and deposition. The concept has also been applied to hill-slopes (‘graded slopes’) that are stable dynamically and so maintain themselves in the most economical configuration. The term is no longer used widely as it oversimplifies the issues involved.

grade

views updated May 18 2018

grade
1. A group of things all of which have the same value.

2. A distinctive functional or structural improvement in the organization of an organism. Thus fish, amphibians, reptiles, and mammals represent successive vertebrate grades. Grades may occur within a single lineage; or the same grade may be achieved independently in differen ones (e.g. warm-bloodedness evolved independently in birds and mammals).

grade

views updated Jun 11 2018

grade A group of organisms that share certain morphological characteristics but are not necessarily related in evolutionary terms. For example, all organisms that possess a coelom can be regarded as a grade. A grade can be contrasted with a clade, which represents phylogenetic lineage.

grade

views updated May 17 2018

grade (grayd) n. the severity of a malignant tumour according to its degree of differentiation. Low-grade tumours closely resemble normal tissues, are well differentiated, and have a good prognosis. High-grade tumours show a poor resemblance to normal tissues, are poorly differentiated, and have a poor prognosis.