1. Not easily perturbed or excited or upset; marked by extreme calm and composure
   "hitherto imperturbable, he now showed signs of alarm"; "an imperturbable self-possession"
   - unflappable

See also: composed, imperturbableness

• slipshod
• slipskin grape
• slipstick
• slipstream
• slipway
• slit
• slit lamp
• slit trench
• slither
• slithering
• slithery
• sliver
• slivery
• slivovitz
• Slo-Bid
• Sloane Ranger
• Sloanea
• Sloanea jamaicensis
• slob
• slobber
• slobber over
• slobberer
• slobbish
• sloe
• sloe gin