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

1) An act of entering, as into a place or upon new duties.
2) A point or place of entering; an opening or passage for entering, as a doorway (Dictionary.com). → entrance pupil, → entrance slit.

M.E. entraunce, from M.Fr. entrance, from → enter + → -ance.

Darâyeš, verbal noun of darâmadan, darâyidan, → enter; darâygâh with space suffix -gâh.

In an → optical system, the image of the → aperture stop formed in → object space. See also → exit pupil.

→ entrance; → pupil.

A thin slit in an opaque screen by which light enters a spectrograph.

→ entrance; → slit.