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

1) To bring to a fine or a pure state; free from impurities.
2) To make more fine, subtle, or precise (Dictionary.com).

→ re-; → fine.

1) Pâludan "to purify, starin, → filter."
2) Nâzokidan, from nâzok "tender, delicate, subtle, neat," → fine.

1) Fineness or elegance of feeling, taste, manners, language, etc.
2) The act or process of refining. the quality or state of being refined.
3) An improved, higher, or extreme form of something.
Math.: A → set whose elements include the elements of a given set (Dictionary.com).

Verbal noun of → refine.