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

1) (v.intr.) To come near or nearer, as in space or time.
(v.tr.) To come or go near or nearer to in quality, character, time, or condition.
2) (n.) The act of drawing near; nearness or close approximation; the method used or steps taken in dealing with or accomplishing.

M.E. approchen, from O.Fr. aprochier, from L. appropiare, from ad- "to" + propius "nearer," comparative of prope "near".

1) Nazdidan from nazd "near," Mid.Pers. nazd, Av. nas- "to come near, approach, reach," nazdišta- "nearest, next," nazdyo "nearer to," compare with Skt. nas- "to approach, to reach" + -idan "infinitive forming suffix".
2) Nazdeš, from nazd, nazdidan + -eš "noun forming suffix."

In astronomy a general term to describe the positions of two or more objects that come unusually near one to another. In particular, regarding an asteroid's position with respect to Earth, when it is within the Moon's orbit.

→ close; → approach.