- Sophistry
- Soft goods
- Soft nothings
- Soft option
- Soft palate
- Soft palates
- Soft pedal
- Soft shoulder
- Soft skills
- Soft spot
- Soft sugar
- Soft tack
- Soft tissues
- Soft water
- Soft witted
- Soft-boiled
- Soft-headed
- Soft-spoken
- Soften
- Softening
- Solid
- Softer sex
- Softhearted
- Softish
- Softly
- Softness
- Software
- Software package
- Software piracy
- Softwood
- Softy
- Soggy
- Soh
- Soho
- Soil
- Soil conservation
- Soil erosion
- Soil science
- Soiled
- Soiled cloth
- Soiree
- Sojoirner
- Sojourn
- Sol
- Solace
- Solace oneself with
- Solanaceous crops
- Solar
- Solar battery
- Solar cell
- Solar constant
- Solar day
- Solar eclipse
- Solar energy
- Solar longitude
- Solar month
- Solar myth
- Solar panel
- Solar plexus
- Solar salt
- Solar system
- Solar year
- Solarism
- Solarium
- Solarization
- Solarize
- Solidarity
- Solidification
- Solidified
- Solidify
- Solidity
- Solidly
- Solidness
- Soliloquize
- Soliloquy
- Solipsism
- Solitaire
- Solitarily
- Solitariness
- Solitary
- Solitary confinement
- Solitary confinment
- Solitary person
- Solitary place
- Soliterraneous
- Solitude
- Solitudinous
- Solo
- Solo rider
- Soloist
- Solstice
- Solstice points
- Solubility
- Soluble
- Solubleness
- Solus
- Solute
- Solution
- Solutive
- Solvable