Body relative directions (also known as egocentric coordinates) are geometrical orientations relative to a body such as a human person's body or a road sign. The most common ones are: left and right; forward and backward; up and down. They form three pairs of orthogonal axes. Traditions and conventions. Since definitions of left and right based on the geometry of the natural environment are unwieldy, in practice, the meaning of relative direction words is conveyed through tradition, acculturation, education, and direct reference.
https://en.wikipedia.org/wiki/Body_relative_direction
Body relative directions (also known as egocentric coordinates) are geometrical orientations relative to a body such as a human person's body or a road sign. The most common ones are: left and right; forward and backward; up and down. They form three pairs of orthogonal axes. Traditions and conventions. Since definitions of left and right based on the geometry of the natural environment are unwieldy, in practice, the meaning of relative direction words is conveyed through tradition, acculturation, education, and direct reference.
