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 "old man") 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. Wikipedia