Six is a number after five and before seven.(noun)
When you have six units of something, you are six years of age, it is six o'clock, or you wear a size six clothing are all examples of six.
See six in Webster's New World College Dictionary
Origin: ME < OE sex, akin to Ger sechs, ON sex, Goth saihs < IE base *seks, *swes > L sex, Gr hex, Sans ṣáṭ
See six in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Old English; see s(w)eks in Indo-European roots.
Learn more about six