1. An opening; a hollow; a bay; a cavity in a bone or other part; a fistula; a groove or cavity.

Nuttall's Standard dictionary of the English language By Nuttall, P.Austin

• sinkis,
• sinors,
• sinze,
• sinusis,
• sinces,
• sinues,
• seious,
• binus,
• sinxw,
• sinsk,
• sinns,
• sinds,
• linus,
• sincse,
• sinnus,
• businus,
• spings,
• siners,
• sinnes,
• sinis

• simes,
• simoes,
• siems,
• SIMS,
• SIMAS,
• SINEs,
• sinuous,
• Simms.

The adjective form of the word "sinus" is "sinusal".

The plural of the "sinus" can be the "sinuses".

The singular of the "sinus" can be the "sinus".