Lewis & Short

sella (ancient collat. form sedda, acc. to Scaur. p. 2252 P.), ae, f. dim. [for sedla; root sed-; .sedes],

  1. I. a seat, settle, chair, stool (syn.: sedile, scamnum): viden’ ut expalluit! datin’ isti sellam, ubi assidat cito, Plaut. Curc. 2, 3, 32; id. Bacch. 3, 3, 28; id. Poen. 1, 2, 56: scabilla, sellas, solia, Cato, R. R. 10, 4; 157, 11: in sellā sedere, Cic. Div. 1, 46, 104 (corresp. to sedes): fracta est patris sella, Petr. 136: altā deducere sellā, Juv. 3, 136 al.
  2. II. Esp.
    1. A. Of a mechanic’s work-stool: ipsum sellae atque operis et quaestus cottidiani locum, Cic. Cat. 4, 8, 17: in foro sellam ponere, id. Verr. 2, 4, 25, § 56.
    2. B. Of a teacher’s chair, Cic. Fam. 9, 18 fin.
    3. C. Of a portable chair or sedan (different from the lectica, a litter made like a bed): aut sellā, aut lecticā transire, Suet. Claud. 25; so (opp. lectica) Dig. 32, 1, 49; Mart. 10, 10, 7; 11, 98, 12; simply sella, Suet. Aug. 53; Plin. Ep. 3, 5, 15; Juv. 1, 124 al.; called also sella gestatoria, Suet. Ner. 26; id. Vit. 16; Vulg. 2 Macc. 3, 27; cf.: gestamen sellae, Tac. A. 14, 4; 15, 57.
    4. D. Of a seat in a coach or wagon, Phaedr. 3, 6, 5.
    5. E. Of a close-stool, Scrib. Comp. 193; 227; also called sella familiarica, Varr. R. R. 1, 13, 4.
  3. F. Of a saddle, Cod. Th. 8, 5, 47; Cod. Just. 12, 51, 12; Veg. 6, 6, 2; Vulg. Esth. 6, 8.
  4. G. Esp., a magistrate’s seat or chair (very freq.), Cic. Phil. 2, 34, 85; id. Div. 1, 52, 119; id. Verr. 2, 1, 46, § 119; 2, 1, 47, § 124; 2, 2, 38, § 94; Caes. B. C. 3, 20; Liv. 3, 11; 6, 15; Hor. S. 1, 6, 97 et saep.; also called sella curulis; v. curulis.
    Prov.: duabus sellis sedere, to sit on two stools, i. e. to keep in with both parties, Laber. ap. Sen. Contr. 3, 18 fin.; id. ap. Macr. S. 2, 3.