The word anatomy comes from the Greek ana-meaning up or through + tome meaning a cutting. Anatomy was once a cutting up because the structure of the body was originally learned through dissecting it. The word histology came from the Greek histo- meaning tissue + logos, treatise.
Definition: Reliability is the degree to which a measurement instrument gives the same results each time that it is used, assuming that the underlying thing being measured does not change.
Reliability is a measure of the internal consistency and stability of a measuring device. Validity gives us an indication of whether the measuring device measures what it claims to. Internal consistency is the degree in which the items or questions on the measure consistently assess the same construct.