[ 'greɪdɪənt ]
■ noun
1》 a sloping part of a road or railway.
↘the degree of such a slope, expressed as change of height divided by distance travelled.
↘ Mathematics the degree of steepness of a graph.
2》 Physics a change in the magnitude of a property (e.g. temperature) observed in passing from one point or moment to another.
Origin
C19: from grade , on the pattern of salient .