- Slantways
- Slash
- Slashed
- Slate-black
- Slaverer
- Slavery
- Slavishly
- Slay
- Sleazy
- Sledge
- Sleekly
- Sleep of the just
- Sleeper
- Sleepiness
- Sleeping around
- Sleeping bag
- Sleeping coach
- Sleeping draught
- Sleeping sickness
- Sleeping suit
- Sleepish
- Sleigh
- Sleight of hand
- Slender person
- Slenderly
- Slenderness
- Slew
- Sliced bread
- Slicing
- Slide valve
- Slide-rest
- Slider
- Slim
- Slimmish
- Slimy
- Slip off
- Slip stream
- Slippage
- Slipshod
- Slittered
- Slobberer
- Slog
- Slop
- Slope
- Slopped
- Slosh
- Spermatogenesis
- Spermatorrhea
- Spermatozoon
- Spherical
- Spherically
- Sphericity
- Spheroid
- Spheroidic
- Sphygmological
- Sphygmomanometer
- Spick
- Spick and span
- Spitted
- Spiffling
- Spigot
- Spikes
- Spill
- Spiracle
- Spilt
- Spinach
- Spinal chord
- Spinal column
- Spine
- Spinelessly
- Spinney
- Spinning mill
- Spinning top
- Spiny
- Spirant
- Spire
- Spirit of sacrifice
- Spirit salts
- Spiritedness
- Spiritual preceptor
- Spiritual strength
- Spiritualism
- Spirituous
- Spirituousness
- Spissitude
- Spit out
- Spite
- Spitfire
- Spluttering
- Splashing
- Splenderous
- Splendid
- Splendidly
- Splendidness
- Splendour
- Splice
- Split file
- Split hairs
- Splotch
- Splurge