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

A member of the most extreme galaxies in terms of their luminosities and unusual hot → dust temperatures. The → infrared emission from HDOGs is dominated by obscured accretion onto a central → supermassive black hole (SMBH), in most cases without significant contribution from → star formation. The large contrast between the underlying → host galaxy and the hyper-luminous emission from the → active galactic nucleus (AGN) implies that either the SMBH is much more massive than expected for the stellar mass of its host, or is radiating well above its → Eddington limit. The most extreme of these remarkable systems known is → W2246-0526.

→ hot; → dust; → obscure; → galaxy.

1a) Lacking in light or illumination; dark; dim; murky.
1b) Indistinct to the sight or any other sense.
1c) Not clear to the understanding.
2) To make dark, dim, indistinct, etc.

From O.Fr. obscur "dark, dim, not clear," from L. obscurus "covered over, dark, obscure," from ob "over" + -scurus "covered," from PIE *(s)keu- "to cover, conceal;" from which derives also the term → sky.

Tiré, from Mid.Pers. târag "dark, turbid," related to târik "dark," Mid.Pers. târig "dark," târ "darkness," Av. taθra- "darkness," taθrya- "dark," cf. Skt. támisrâ- "darkness, dark night," L. tenebrae "darkness," Hittite taš(u)uant- "blind," O.H.G. demar "twilight."
Tiré kardan compound verb with kardan "to do," → -ize.