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

A substance or phenomenon whose presence in an object such as a → meteorite or an → exoplanet indicates the existence of life.

→ bio-; → signature.

The natural world as it exists without human beings or civilization.

M.E. natur(e), from O.Fr. nature from L. natura "the things at the outset, as it was when brought into existence; conditions of birth; essence, natural qualities," from natus "born," p.p. of nasci "to be born," from PIE *gen- "to give birth, beget," cognate with Pers. zâdan "to give birth," as below.

Zâstâr, literally "birth," from zâst past stem of [Dehxodâ] zâstan, variant of zâdan "to bring forth, give birth;" (Lâsgardi, Sorxeyi, Aftari) nestor "barren, sterile" (Mid.Pers. zâtan; Av. zan- "to bear, give birth to a child, be born," infinitive zazāite, zāta- "born;" cf. Skt. janati "begets, bears;" L. gignere "to beget," nasci "to be born," as above, PIE base *gen- "to give birth, beget") + suffix -âr (forming verbal nouns as in raftâr, kerdâr, goftâr, didâr, jostâr, and so on; or forming accusative nouns, as in gereftâr, koštâr, etc.).

A general term to describe → light involving the following phenomena: → reflection, → refraction, and → photoelectric effect. Compare → wave nature.

→ particle; → nature.

1) Physics, Chem.: A distinctive trace or sign that indicates the presence of a substance or the occurrence of a physical process or event.
2) Telecommunication: The complete set of electromagnetic and/or acoustic signals received, e.g., from an infrared source, a radio or radar transmitter, an aircraft, or a ship. Signatures may consist of analog or digital signals, or both, and may be analyzed to indicate the nature of their source and assist in its recognition.

M.Fr. signature, from M.L. signatura "sign," in classical L. "the matrix of a seal," from signatus, p.p. of signare "to mark, sign," → sign.

Nešânzad, literally "striking a mark, sign" (cf. angošt zadan "fingerprint"), from nešân, → sign, + zad past stem of zadan "to strike, beat; to do; to play an instrument" (Mid.Pers. zatan, žatan; O.Pers./Av. jan-, gan- "to strike, hit, smite, kill" (jantar- "smiter"); cf. Skt. han- "to strike, beat" (hantar- "smiter, killer"); Gk. theinein "to strike;" L. fendere "to strike, push;" Gmc. *gundjo "war, battle;" PIE *g^when- "to strike, kill").

A general term to describe → light involving the following phenomena: → reflection, → refraction, → interference, → diffraction, and → polarization. Compare → particle nature.

→ wave; → nature.