sōlārĭum (noun N) : id..
* (Sc. horologium, which is expressed in Plin. 7, 60, 60, § 213.) A sundial: solarium dictum id, in quo horae in sole inspiciebantur, etc.,Varr. L. L. 6, § 4 Müll.: ut illum Di perdant, primus qui horas repperit, Quique adeo primus statuit hic solarium, Plaut. Fragm. ap. Gell. 3, 3, 5; cf. Becker, Gallus, 2, p. 301 sq. (2d ed.): venter erat solarium, Aquil. ib. 3, 3, 4.
* Transf.
* A part of the house exposed to the sun, a flat house-top, a terrace, balcony, or the like, Plaut. Mil. 2, 3, 69; 2, 4, 25; Aug. ap. Macr. S. 2, 4; Suet. Ner. 16; id. Claud. 10; Pall. Mai, 11, 1; Vulg. 2 Reg. 16, 22; id. Jos. 2, 6; Dig. 8, 2, 17; Inscr. Orell. 3303; 4240; Isid. Orig. 15, 3 al.; cf. Becker, Gallus, 2, p. 200 sq. (2d ed.).—Also on sepulchral monuments,Inscr. Orell. 4536.
* A clock in gen. (even a water-clock): cum solarium aut descriptum aut ex aquā contemplere,Cic. N. D. 2, 34, 87; cf. Censor. de Die Nat. 23 fin.

sŏlārium (noun N) : (sc. vectigal), solum
* A ground-rent, Dig. 43, 8, 2, § 17; 7, 1, 7, § 2; 13, 7, 17; 30, 1, 39, § 5; Inscr. Orell. 39; cf. Becker, Antiq. 3, 2, p. 121, n. 614.