- singer
- single someone, something out
- single-handed
- single-minded
- singular
- singularity
- sinister
- sink
- sinking fund
- sinuous
- sinusoidal
- sip
- siren
- sister
- sister-in-law
- sister-like
- sit
- sit back
- sit tight
- sitar
- site
- sitting
- sitting cross-legged
- sitting room
- situate
- situation
- situation comedy
- six
- six heinous mentioned in the holy scriptures
- sizeable
- sizzling
- skater
- skedaddle
- skeletal
- sketch
- sketchy
- skew-whiff
- skiable
- skid road
- skilful
- skilful physician
- skilled
- skim
- skimpy
- skinflint
- skinny
- skip
- skip jack
- skirmisher
- skirt
- skittish
- skive
- skulk
- skulking place
- skull
- sky
- skyre
- slack
- slack away
- slack up
- slack-water
- slacken
- slacker
- slag someone off, slag something off
- slake
- slakeless
- slam
- slam the door
- slander
- slanderous
- slanging match
- slant
- slap
- slap someone down
- slap-happy
- slap-up
- slasher
- slate
- slate-coloured
- slatternly
- slaughterhouse
- slave
- slaverer
- slavery
- slaying
- sleazy
- sledge
- sleek
- sleek-headed
- sleep of the just
- sleepiness
- sleeping beauty
- sleeplessness
- sleepwalker
- sleepy
- slender
- sleuth
- slice
- slick
- slide-rest