Humanoid

A humanoid is an intelligent bilaterally symmetrical, bipedal lifeform in possession of an upright posture, two arms, two legs, hands, feet, one thorax, a neck, and a head with a brain located in it. They are generally mammalian and originate on Class M planets. It is common for them to have two sexes. Among the many humanoid species known throughout the Milky Way Galaxy are Andorians, Bolians, Bajorans, Klingons, Humans, and the Vulcans.

Despite the vast distances separating their homeworlds, many humanoid species have been found to share a remarkable commonality in form and genetic coding. These similarities were believed to be evidence of a common ancestry, an ancient humanoid species, who lived in our galaxy's distant past some four billion years ago.

This information taken from http://memory-alpha.org