ātrĭum (noun N) : acc. to Scaliger, from αἴθριον, subdiale, since it was a part of the uncovered portion of the house (but the atrium of the Romans was always covered); acc. to Varr. L. L. 5, § 161 Müll., from the Tuscan town Atria, where this style of architecture originated; cf. Paul. ex Fest. p. 13 Müll.; and Müller, Etrusk. 1, p. 254 sq.; but better from ater, acc. to the explanation of Servius: ibi etiam culina erat, unde et atrium dictum est; atrum enim erat ex fumo, ad Verg. A. 1, 730.
* The fore-court, hall, entrance-room, entry; that part of the Roman house into which one first came after passing the entrance (janua); cf. Vitr. 6, 4; O. Müller, Archaeol. III. § 293, and Etrusk. above cited. In earlier times, the atrium was used as a dining-room, Cato ap. Serv. ad Verg. A. 1, 726. Here stood, opposite the door, the lectus genialis, Hor. Ep. 1, 1, 87; here sat the housewife with her maidens spinning,Arn. adv. Gent. 2, 67; here clients were in attendance,Hor. Ep. 1, 5, 31; Juv. 7, 7 and 91; and here hung the family portraits and other paintings,Plin. 34, 8, 19, § 55; Mart. 2, 90; Val. Max. 5, 8, 3; Vulg. Matt. 26, 58; ib. Marc. 14, 54; ib. Joan. 18, 15 al.—Poet. in the plur., of a single atrium: Apparet domus intus et atria longa patescunt,Verg. A. 2, 483; so Ov. M. 14, 260; Juv. 8, 20 al.—Meton. for the house itself: nec capient Phrygias atria nostra nurus,Ov. H. 16, 184; id. M. 13, 968.—So of the entrance-room in the dwelling of the gods: dextrā laevāque deorum Atria nobilium (as it were clients, v.supra) valvis celebrantur apertis, Ov. M. 1, 172; Stat. Th. 1, 197.
* In temples and other public buildings there was often an atrium, a hall, court: in atrio Libertatis,Cic. Mil. 22, 59; Liv. 25, 7; 45, 15; Tac. H. 1, 31; Suet. Aug. 29: Vestae,Plin. Ep. 7, 19, 2; also called atrium regium,Liv. 26, 27; cf. Ov. F. 6, 263; id. Tr. 3, 1, 30: atrium tabernaculi,Vulg. Exod. 27, 9; ib. Lev. 6, 26: in atriis Domūs Dei,ib. Psa. 91, 14; 134, 2; Smith, Dict. Antiq.—So atrium auctionarium,an auction-hall, auction-room,Cic. Agr. 1, 3; so Inscr. Orell. 3439; and absol., atria: cum desertis Aganippes Vallibus esuriens migraret in atria Clio,Juv. 7, 7. Such halls were the Atria Licinia, Cic. Quinct. 6, 25: ATRIVM SVTORIVM, the shoemakers' hall, a place in Rome, Calend. Praenest. Inscr. Orell. II. 386.

s. TLL