A senate is a deliberative assembly, often the upper house or chamber of a bicameral legislature or parliament. The name comes from the ancient Roman Senate (Latin: Senatus), so-called as an assembly of the senior (Latin: senex meaning "the elder" or "the old one") and therefore allegedly wiser and more experienced members of the society or ruling class.
Thus, the literal meaning of the word "senate" is: Assembly of Elders.
Many countries have an assembly named a senate, composed of senators who may be elected, appointed, have inherited the title, or gained membership by other methods, depending on the country. Modern senates typically serve to provide a chamber of "sober second thought" to consider legislation passed by a lower house, whose members are usually elected.
The modern word Senate is derived from the [Latin] word senātus (senate), which comes from senex, “old man”. The members or legislators of a senate are called senators. The Latin word senator was adopted into English with no change in spelling. Its meaning is derived from a very ancient form of social organization, in which advisory or decision-making powers are reserved for the eldest men. For the same reason, the word senate is correctly used when referring to any powerful authority characteristically composed by the eldest members of a community, as a deliberative body of a faculty in an institution of higher learning is often called a senate. This form adaptation was used to show the power of those in body and for the decision-making process to be thorough, which could take a long period of time. The original senate was the Roman Senate, which lasted until 580 (various efforts to revive it were made in Medieval Rome). In the Eastern Roman Empire, the Byzantine Senate continued until the Fourth Crusade, circa 1202–1204.