sigm - somn
- sigma
- sigmoid
- sigmoid colon
- sigmoid flexure
- sigmoid mesocolon
- sigmoid notch
- sigmoidectomy
- sigmoiditis
- sigmoidoscope
- sigmoidoscopy
- sigmoidostomy
- sign
- sign language
- sign-off
- sign-on
- signal molecule
- signal-to-noise ratio
- signature
- significance
- silanization
- silent disease
- silent ischemia
- silent mutation
- silent myocardial infartion
- silent peritonitis
- silhouette sign
- silica gel
- silicate dental cement
- silicic acid
- silicon
- silicone
- silicone septum
- silicone-gel breast implant
- silicosis
- silk suture
- silo filler's disease
- silver
- silver amalgam
- silver cone method
- Silver dwarf
