An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

Pertaining to or of the nature of a tangent.

→ tangent + -ial variant of → -al.

That component of a an object's motion which is perpendicular to the observer's → line of sight.

→ tangential; → motion.

1) The instantaneous linear velocity of a body moving in a circular path. It is equal to the → angular velocity multiplied by the radius: v_t = ωr.
3) The component of the velocity of an object, such as a star, that is at right-angles to the observer's → line of sight; also known as transverse velocity. See also → radial velocity.

→ tangential; → velocity.

The → linearly polarized light that vibrates perpendicularly to an imaginary line joining the source to the point of observation.

Tangentially, adverb of → tangential; → polarized; → light.