Your ShelfYour Projects
Webster's Dictionary (1865)

Sī'nus, n.

noun

n.; Lat. pl. SĪ'NUS; Eng. pl. SĪ'NUS-ES. [Lat., a bent surface, a curve, the folds or bosom of a garment, &c., a bay.]

  1. An opening; a hollow; a bending.
  2. A bay of the sea; a recess in the shore, or an opening into the land.
  3. (Anat.) (a.) A cavity in a bone or other part, wider at the bottom than at the entrance. (b.) A venous canal into which several vessels empty themselves. (c.) The bosom. Dunglison.
  4. (Surg.) A little elongated cavity, in which pus is collected; an elongated abscess with only a small orifice.
  5. (Bot.) A hollow of a curved or rounded figure between two projecting lobes. Gray.
  6. (Conch.) A groove or cavity. Humble.